Traps

Traps can be found almost anywhere. One wrong step in an ancient tomb might trigger a series of scything blades, which cleave through armor and bone. The seemingly innocuous vines that hang over a cave entrance might grasp and choke anyone who pushes through them. A net hidden among the trees might drop on travelers who pass underneath. In a fantasy game, unwary adventurers can fall to their deaths, be burned alive, or fall under a fusillade of poisoned darts.

A trap can be either mechanical or magical in nature. Mechanical traps include pits, arrow traps, falling blocks, water-filled rooms, whirling blades, and anything else that depends on a mechanism to operate. Magic traps are either magical device traps or spell traps. Magical device traps initiate spell effects when activated. Spell traps are spells such as glyph of warding and symbol that function as traps.

Traps in Play

When adventurers come across a trap, you need to know how the trap is triggered and what it does, as well as the possibility for the characters to detect the trap and to disable or avoid it.

Triggering a Trap

Most traps are triggered when a creature goes somewhere or touches something that the trap’s creator wanted to protect. Common triggers include stepping on a pressure plate or a false section of floor, pulling a trip wire, turning a doorknob, and using the wrong key in a lock. Magic traps are often set to go off when a creature enters an area or touches an object. Some magic traps (such as the glyph of warding spell) have more complicated trigger conditions, including a password that prevents the trap from activating.

Detecting and Disabling a Trap

Usually, some element of a trap is visible to careful inspection. Characters might notice an uneven flagstone that conceals a pressure plate, spot the gleam of light off a trip wire, notice small holes in the walls from which jets of flame will erupt, or otherwise detect something that points to a trap’s presence.

A trap’s description specifies the checks and DCs needed to detect it, disable it, or both. A character actively looking for a trap can attempt a Wisdom (Perception) check against the trap’s DC. You can also compare the DC to detect the trap with each character’s passive Wisdom (Perception) score to determine whether anyone in the party notices the trap in passing. If the adventurers detect a trap before triggering it, they might be able to disarm it, either permanently or long enough to move past it. You might call for an Intelligence (Investigation) check for a character to deduce what needs to be done, followed by a Dexterity check using thieves’ tools to perform the necessary sabotage.

Any character can attempt an Intelligence (Arcana) check to detect or disarm a magic trap, in addition to any other checks noted in the trap’s description. The DCs are the same regardless of the check used. In addition, dispel magic has a chance of disabling most magic traps. A magic trap’s description provides the DC for the ability check made when you use dispel magic.

In most cases, a trap’s description is clear enough that you can adjudicate whether a character’s actions locate or foil the trap. As with many situations, you shouldn’t allow die rolling to override clever play and good planning. Use your common sense, drawing on the trap’s description to determine what happens. No trap’s design can anticipate every possible action that the characters might attempt.

You should allow a character to discover a trap without making an ability check if an action would clearly reveal the trap’s presence. For example, if a character lifts a rug that conceals a pressure plate, the character has found the trigger and no check is required.

Foiling traps can be a little more complicated. Consider a trapped treasure chest. If the chest is opened without first pulling on the two handles set in its sides, a mechanism inside fires a hail of poison needles toward anyone in front of it. After inspecting the chest and making a few checks, the characters are still unsure if it’s trapped. Rather than simply open the chest, they prop a shield in front of it and push the chest open at a distance with an iron rod. In this case, the trap still triggers, but the hail of needles fires harmlessly into the shield.

Traps are often designed with mechanisms that allow them to be disarmed or bypassed. Intelligent monsters that place traps in or around their lairs need ways to get past those traps without harming themselves. Such traps might have hidden levers that disable their triggers, or a secret door might conceal a passage that goes around the trap.

Trap Effects

The effects of traps can range from inconvenient to deadly, making use of elements such as arrows, spikes, blades, poison, toxic gas, blasts of fire, and deep pits. The deadliest traps combine multiple elements to kill, injure, contain, or drive off any creature unfortunate enough to trigger them. A trap’s description specifies what happens when it is triggered.

The attack bonus of a trap, the save DC to resist its effects, and the damage it deals can vary depending on the trap’s severity. Use the Trap Save DCs and Attack Bonuses table and the Damage Severity by Level table for suggestions based on three levels of trap severity.

A trap intended to be a setback is unlikely to kill or seriously harm characters of the indicated levels, whereas a dangerous trap is likely to seriously injure (and potentially kill) characters of the indicated levels. A deadly trap is likely to kill characters of the indicated levels.

Table: Trap Save DCs and Attack Bonuses

Trap Danger	Save DC	Attack Bonus
Setback	10–11	+3 to +5
Dangerous	12–15	+6 to +8
Deadly	16–20	+9 to +12

Table: Damage Severity by Level

Character Level	Setback	Dangerous	Deadly
1st–4th	1d10	2d10	4d10
5th–10th	2d10	4d10	10d10
11th–16th	4d10	10d10	18d10
17th–20th	10d10	18d10	24d10

Sample Traps

Traps vary in deadliness and are grouped by type (magic or mechanical) and then in alphabetical order. First listed are mechanical traps, then magical traps. Then, Hazards (like haunts), are listed next.

Traits

The line following the trap/hazard name is a list of traits that apply to that trait.

Magic

The magic trait…

Mechanical

The magic trait…

Mechanical and Magic Traps

Some traps have traits both mechanical and magical. They have both Magic and Mechanical traits and follow rules for both.

Simple Complexity

The simple trait…

Complex Complexity

Traps with the Complex trait work like those with the Simple trait, except once activated they execute a series of actions each round. A complex trap turns the process of dealing with a trap into something more like a combat encounter.

When a complex trap activates, it rolls initiative. The trap’s description includes an initiative bonus. On its turn, the trap activates again, often taking an action. It might make successive attacks against intruders, create an effect that changes over time, or otherwise produce a dynamic challenge. Otherwise, the complex trap can be detected and disabled or bypassed in the usual ways.

For example, a trap that causes a room to slowly flood works best as a complex trap. On the trap’s turn, the water level rises. After several rounds, the room is completely flooded.

Haunt

Haunts include supernatural or psychic-like components, or which are triggered by such. Haunts have unique defeat rules.

Trap

This trait separates a “trap” from a hazard like poison, disease, or otherwise passive environmental danger. Traps are intentionally designed to thwart, slow, delay, injure, kill, or more.

Mechanical Traps

The following traps do not include any magical or supernatural components. They are completely constructed of mundane, mechanical components.

Falling Net

Mechanical Trap

This trap uses a trip wire to release a net suspended from the ceiling.

The trip wire is 3 inches off the ground and stretches between two columns or trees. The net is hidden by cobwebs or foliage. The DC to spot the trip wire and net is 10. A successful DC 15 Dexterity check using thieves’ tools breaks the trip wire harmlessly. A character without thieves’ tools can attempt this check with disadvantage using any edged weapon or edged tool. On a failed check, the trap triggers.

When the trap is triggered, the net is released, covering a 10-foot-square area. Those in the area are trapped under the net and restrained, and those that fail a DC 10 Strength saving throw are also knocked prone. A creature can use its action to make a DC 10 Strength check, freeing itself or another creature within its reach on a success. The net has AC 10 and 20 hit points. Dealing 5 slashing damage to the net (AC 10) destroys a 5-foot-square section of it, freeing any creature trapped in that section.

Falling Stone Blocks

Source TM

Mechanical Trap

When a creature steps on a pressure plate with more than 20 lbs of force (or, in the case of weak construction, causes a large vibration by, for example, casting thunder wave), several stone blocks fall from the ceiling in a 10-foot radius around the creature. Each creature within the circle must make a DC 15 Dexterity saving throw. Those who fail the saving throw take 18 (4d8) bludgeoning damage while those who succeed take half this amount. The unstable state of the ceiling can be identified with a successful DC 14 Intelligence (Investigation) check.

Finding the pressure plate requires a DC 15 Wisdom (Perception) check.

The Drop and Plop CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. A pitfall trap that has a perfectly fitting gelatinous cube inside it. The pit is 10 feet by 10 feet and has a trap door at the top.

Trigger. One hundred pounds of pressure applied to the trap door (for instance, someone stepping on it), causes the trap door to open. Victims must make DC 14 Dexterity saving throw or fall in. The gelatinous cube immediately attacks anyone who falls in and automatically gains surprise.

Countermeasures. A DC 15 Wisdom (Perception) check reveals the presence of the trap door on the floor. Jumping over the trap door bypasses it, or a DC 14 Dexterity (Thieves Tools) check disables the trap door.

The Jelly Jamb CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. There is a glass pot of ooze above a door that triggers when the door is opened. The pot falls and shatters, releasing 1d4+1 ochre jellies that then attack the PCs!

Trigger. When the door is opened, the pot falls and breaks.

Countermeasures. The character that opens the door sees the pot falling. If they succeed on a DC 15 Dexterity saving throw, they can catch the pot if they want. The pot weighs 200 pounds and a character who catches it must make a DC 17 Strength (Athletics) check to not drop it and cause it to shatter.

Rusty Stuffings CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. In the corridor is a small, pink toy bear.

It’s actually a rust monster that has been polymorphed into a toy bear and is incapacitated while in that form.

The polymorph wears off five minutes after the toy bear has been placed into a container of any kind, such as a backpack. The rust monster then promptly begins to devour all metal items it can.

Countermeasures. Casting detect magic reveals a transmutation aura around the bear. The identify spell reveals the exact nature of the trap.

Golden Eye CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. A solid gold sphere sits in the middle of the room. When the sphere is touched, it opens, revealing a Death Kiss which promptly attacks.

Countermeasures. A successful DC 16 Wisdom (Perception) check reveals fine seams along the exterior of the sphere, indicating that it can be opened. Detect magic reveals an aura of abjuration about the sphere. A successful DC 13 Intelligence (Investigation) check reveals that the sphere is not made of gold, but iron painted over with gold.

Gold Dust Shroom Boom CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. Golden mushrooms are growing along the bottom of a chest, stretching about halfway up.

Below the mushrooms a large pile gold sparkles and beckons to the characters.

Trigger. Touching the mushrooms causes them to release a cloud of poisonous spores in a 10-foot radius. Everyone caught in the effect takes 2d6 poison damage or half as much if they succeed on a DC 12 Constitution saving throw. Once the spore cloud has been triggered, it takes 1d4 hours for the mushrooms to create more spores.

Countermeasures. A successful DC 13 Intelligence (Nature) check reveals that the poisonous nature of the mushrooms, including that it takes time to regenerate more spores once triggered.

The DoppelDoor CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Purpose. There is a magical doorway that teleports the first character to step through it into a pocket dimension (per the banishment spell) and replaces them with a doppelganger that looks exactly like them.

This effect lasts until the doppelganger dies, at which point the character is teleported to where the doppelganger perishes, taking the place of its body.

When this happens, the game master should take the player whose character was replaced away from the group, explain what has happened, and let them play the doppelganger. The GM should give the player some basic information to inform their roleplaying, such as the doppelganger’s motivations.

Countermeasures. A character who is suspicious of the doppelganger can make a Wisdom (Insight) check contested by the doppelganger’s Charisma (Deception) check. If the character wins, he notices small imperfections with the doppelganger’s disguise or acting, cluing him in that it is not actually the character.

The BrainWasher

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. In a room is a sink full of dirty dishes. A character who comes within 10 feet of the dishes feels magically compelled to clean them. They must succeed on a DC 15 Wisdom saving throw or be compelled to clean the dishes, a task that takes the next 15 minutes. If the character takes damage, they may repeat the saving throw, breaking out of the enchantment on a success.

At the end of 15 minutes, when the dishes have been cleaned, more dirty dishes magically fill the sink, and the character, and any others within range must make a new saving throw or be compelled to clean the dishes.

Countermeasures. Detect magic reveals an aura of enchantment magic around the dishes. Breaking all of the dishes causes the magic to fail, releasing anyone caught in its thrall.

Mimic Madness CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. A hallway contains three mimics that are concealing themselves as parts of the walls, floors, and doors. When the party is in the middle of the hallway, they attack.

Pleased to Meet You CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. A pair of large disembodied hands float in front of and block a passage. To get past, the characters must shake hands with them. If the hands are attacked or someone tries to push them out of the way, the hands slap the offenders. They have a +8 to hit and deal 4d10 bludgeoning damage.

Countermeasures. The characters notice an inscription on the wall near the hands that reads, “Foes don’t proceed; only friends shall we be.” This a clue that they need to shake the hands.

Fool’s Gold CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap (level 5-10, dangerous)

Description. A pot of gold coins sits on a table in a room. A character that removes gold from the pot must make a DC 15 Intelligence saving throw or suffer a hallucination that leprechauns are attacking them.

Countermeasures. Detect magic reveals an aura of enchantment magic around the pot. Placing the gold back into the pot releases the character from the hallucination. The hallucinations also wear off after 1d4+1 minutes.

The Baynard Curtain CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Purpose. Mark the characters so that they are easier for enemies to hit in combat.

Trigger. Vines over the mouth of the cave are tripwires that release buckets of phosphorescent powder.

Effect. Characters within 15 feet are covered in a phosphorescent powder that gives monsters using darkvision advantage on their Attack rolls against the characters for the next 1d4 hours if they fail a DC 14 Dexterity saving throw.

Countermeasures. The vine tripwires can be detected with a successful DC 13 Wisdom (Perception) check.

The tripwires can be disabled with a DC 12 Dexterity (Thieves Tools) check. Characters proficient in Nature have advantage on all interactions with the vines.

The powder can be removed from a character using a gallon of alcohol, such as ale, to clean it off.

GM Note. Combine this trap with guardians in the entrance of the cave that use darkvision. Thus, the trap makes the PCs more vulnerable to the guardians.

The Yeeter Totter CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Complex Mechanical Trap

Purpose. To throw PCs off the bridge and prevent them from passing.

Trigger. In the middle of the bridge on the railing is a small sign that reads “None Shall Pass.” These are magical letters, that when read causes the trap to spring.

Effect. When triggered, violent waves travel down the bridge for one round (6 seconds), causing the bridge to bounce up and down, similar to a trampoline. Players must succeed on a DC 15 Dexterity saving throw or be bounced off the edge of the bridge and be dangling from the side while grabbing the ropes. On the next round, dangling players must succeed on a DC 15 Strength saving throw or fall. Players who succeed on this saving throw are able to pull themselves back onto the bridge. Players who are not bucked off the bridge can help dangling players get back up, granting them advantage on their Strength saving throw.

Countermeasures. Detect magic will indicate that the entire bridge is covered in transmutation magic. Casting Dispel Magic will suppress the trap for 1d4+2 minutes. Casting Dispel Magic at level 5 or above, permanently dispels the trap.

Not Silent, Just Deadly CR 11-16

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Purpose. This is an ornate throne, designed to kill people.

Trigger. When someone sits on the throne, there is a squish as a sticky substance on the throne immediately bonds to the pants of the person sitting on the throne. Standing up from the throne pulls a pressure plate upwards, triggering the trap.

Effect. When triggered, a loud farting noise is emitted from the bottom of the throne as a large bladder full of poisonous gas is released into the room. Characters within 15 feet of the throne must make a DC 17 Constitution saving throw, taking 99 (18d10) poison damage on a failed save or half that damage on a successful save.

Countermeasures. Someone sitting on the throne can remove their pants to then get out of the throne without triggering it.

GM Note. Make there be an enticing reason that a character would want to sit in this throne. For instance, a sign reading “Don’t Sit Here” or “Free Gold” hanging above the throne might entice them to sit on it. Or you might make sitting on the throne seem necessary to advance in the dungeon, such as implying that it opens a secret door or something.

Scabaited CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

The sword itself is not magical. However, the scabbard emanates evocation magic when detect magic is used. Characters handling the scabbard can tell that it is magical, too. (This will probably make the character think the sword is magical.)

Purpose. Punish thieves who take the sword.

Trigger. Pulling the sword from the scabbard without first whispering the command phrase “Here I go killing again” triggers the trap.

Effect. Magical runes on the scabbard detonate, causing the scabbard to explode into a cloud of shrapnel, dealing 4d10 slashing damage to all creatures within 10 feet. Creatures who succeed on a DC 14 Dexterity saving throw take half damage.

Countermeasures. Casting detect magic reveals evocation magic on the scabbard. A successful DC 15 Intelligence (Arcana) check while studying the runes on the scabbard reveals that it explodes when the sword is drawn. Casting identify on the scabbard or sword (before drawn) reveals the command phrase.

The Bunny Blunder CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

There is a rope hanging from the ceiling with a golden carrot worth 50 gp tied to the end of it.

Purpose. To reward players with pain and suffering for being foolish enough to pull on a rope and carrot hanging from the ceiling.

Trigger. Pulling on the rope or removing the carrot from the rope.

Effect. A trap door opens on the ceiling, raining down 2d6 Killer Bunnies!

Countermeasures. A character searching the ceiling and succeeding on a DC 13 Wisdom (Perception) check notices that there is the outline of a trap door on the ceiling. Characters can bypass the trap by not pulling on the rope.

GM Note. Use the stat block for giant rat for the Killer Bunnies.

Octonote CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. A brass flute rests on a pedestal before a locked door. Playing any eight notes on the flute unlocks the door. Playing any other number of notes magically causes the hallway to fill with water and 1d4+2 giant octopuses that attack. Carved into the side of the pedestal are depictions of underwater scenes and aquatic creatures. Characters who succeed on a DC 14 Intelligence (Investigation) check while examining the pedestal discover that there are eight musical notes hidden among the carvings on the pedestal. Character proficient with a musical instrument gain advantage on the check.

Bark or Bite CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. There is a door with beautiful forest scenery carved into it, but it has no doorknob. Carved in the doorframe above the door in elven is “Be polite or I bite.”

Trigger. The door must be verbally asked to open in elven, and when someone does so, it swings open. However, anyone trying to open the door by physical means causes one swarm of insects (beetles) to burrow out from within the door and attack.

Bee-ware CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. This is a locked puzzle box always accompanied by a pot of honey that players might find among other loot. Every so often a BEEping sound emanates from a small hole on one side of the box. If characters look into the hole, they can see some treasure inside (see below). Touching the puzzle box leaves a sticky feeling on your hands. Smelling or tasting the substance reveals it is sweet like honey.

The game master should place level-appropriate loot in the puzzle box for players to be rewarded with.

Trigger. The puzzle box opens when honey from the pot is poured into a small hole on one side. When opened, a swarm of bees (use the stat block for swarm of insects (wasps)) emerges and attacks the character who has the pot of honey. If no one took the pot of honey, the wasps fly away.

Countermeasures. A character who inspects the box and the hole on its side spots the swarm of bees inside the box on a successful DC 12 Wisdom (Perception) check. Characters might use various methods to avoid being attacked by the bees. However, blowing smoke into the hole placates the bees, making them docile when the box is opened.

Double Vision CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. There is a mirror on the ceiling.

Trigger. When a character’s reflection is shown in the mirror by stepping below it, the character must make a DC 15 Charisma saving throw. On a failed save, the character is instantly teleported inside the mirror, and a doppelganger appearing exactly like the character takes their place. The character is trapped in the mirror in a sort of magical demi-plane until the doppelganger dies. Only one character at a time can be affected by this.

GM Note: When a character is swapped with the doppelganger, take the player aside and explain what happened in secret. Then have that player roleplay the doppelganger. That way the player isn’t just sitting out and doing nothing.

Countermeasure. Breaking the mirror nullifies the trap. If the mirror is broken while a PC is trapped within, they are released from within.

Over the Rainbow CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. There is a hallway with a floor painted with stripes of all the different colors of the rainbow.

Trigger. Walking on an incorrect stripe (any except red) at the midpoint of the hallway causes multicolored bolts of energy to shoot from the ceiling above at all characters in the hallway. The characters must make a DC 15 Constitution saving throw, taking 4d10 poison damage on a failed save, or half that much on a successful save.

GM Note: If desired, make the type of damage correspond to the color of the stripe the PC is walking on. Blue is electric, green poison, purple force, etc.

Countermeasures. Written in Draconic along the edge of the floor just before the hallway begins is “It’s Red or you’re Dead.” Characters succeeding on a DC 13 Wisdom (Perception) check notice this writing. If the characters only walk on the red stripe, the bolts of energy do not trigger.

e-MACE-iation CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. This appears to be a +1 mace when identified. However, it is a trap!

Trigger. Every time the mace is used in combat and successfully hits its target, roll a d12. On a 10, 11, or 12, the head of the mace explodes throwing shrapnel all about. Every creature in a 15-foot radius must make a DC 13 Dexterity saving throw, taking 2d6 piercing on a failed save, and half as much on a successful save. The wielder of the mace has disadvantage on the saving throw.

Countermeasures. A successful DC 12 Intelligence (Investigation) check reveals that the head of the mace is not stable and designed to break apart.

Piggy Bank

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. There is a hog on a spit roasting over a fire. The fire is illusory, as is the smell of beautiful bacon that fills the room. Characters interacting with the roasting hog recognize it for an illusion. The hog is actually a treasure chest filled with loot of the game master’s choice.

Trigger. When a character reaches through the hog’s mouth to extract the treasure, they must succeed on a DC 14 Wisdom saving throw or be polymorphed (per the spell) into a pig for 1d4 hours.

Countermeasures. A player who succeeds on a DC 14 Intelligence (Arcana) check notices magical runes carved into the flesh of the roasting hog, indicating the presence of some sort of polymorph effect. Casting dispel magic on the hog disables the trap for 1 hour.

Also, the loot can be successfully extracted from the piggy bank by reaching not through the mouth, but the other end. A successful DC 12 Wisdom (Perception) check reveals the presence of a small tag on one of the hog’s ears that reads, “Try the other end.”

Red Hots CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. A small jar contains 2d6 jellybeans.

Trigger. The beans are actually fireball pellets, albeit delicious ones. If a bean is eaten, a fireball immediately explodes in the consumer’s mouth. A fireball (per the spell, DC 16) goes off, centered on the person eating the bean. The person eating the bean automatically fails the saving throw. If the entire jar of beans is dumped out, all of them immediately detonate. (TPK baby! Lol)

Effect. The fireball jellybeans can be thrown up to thirty feet and explode per the fireball spell (save DC 16).

Countermeasures. Stop being dumb and eating weird food you find in dungeons!

Boots of Sticking and Snaring CR 11-16

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. There is a finely made pair of boots with magical aura cast on them, making them appear to be boots of striding and springing.

Trigger. There are small pressure plates in the heels of the boots. When someone puts the boots on and walks in them, the trap is triggered.

Effect. When triggered, sovereign glue oozes from the soles of the boots, on both the inside and the outside. It adheres fast to the PC’s foot and the floor, rooting them in place. The sovereign glue used in this trap sets in six seconds instead of one minute. (Once the glue has been used, it’s gone.) When triggered, the character feels something wet inside the boot and the boots seem to stick a little to the ground. If the character tries to remove the boots immediately, they must succeed on a DC 17 Strength saving throw in order to do so before the glue sets.

Countermeasures. A successful DC 15 Wisdom (Perception) check reveals that the soles of the boots are abnormally thick. Upon examining the thick soles, a successful DC 18 Intelligence (Investigation) check reveals the presence of a hidden compartment in the soles and how to open it. Inside the compartment on each boot is a bottle of sovereign glue for the taking, as long as the trap isn’t triggered first, which deploys the glue.

Mace-in-a-Box CR 1-4

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. A non-descript chest with no visible lock.

Trigger. Opening the lid triggers the trap.

Effect. When triggered, a spring-loaded mace inside the lid swipes in an arc at anyone standing in front of the chest. The mace has an attack bonus of +5 and on hit deals 4 (1d8) bludgeoning damage and the target must make a DC 14 Constitution saving throw. On a failed save, the target takes 7 (2d6) poison damage and is poisoned for one minute. On a successful save, the target takes half damage and is not poisoned.

Countermeasures. Opening the chest from the side or at range (such as with a ten-foot pole) bypasses the swinging mace. A successful DC 12 Wisdom (Perception) check reveals the presence of buckling wood on the backside of the lid as though something inside were pulling on the wood. A successful DC 13 Dexterity (Thieves’ Tools) check can disarm the trap.

Helm of the Catfolk CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Magic Trap Simple

Description. There is a finely made helmet shaped like the head of a jaguar with eyes of emerald on a pedestal worth roughly 200 gp.

Trigger. Removing the helmet from the pedestal trips a pressure plate which triggers the trap.

Effect. The character who moved the helmet is targeted by a polymorph spell. The character must make a DC 16 Wisdom saving throw. On a failed save, the character is polymorphed into a tiny cat for 1d4 hours. If as a cat the character is reduced to 0 hit points, they just turn into a different breed of cat. This can happen up to nine times, and on the tenth time of being reduced to 0 hit points, the character reverts to their normal self. Otherwise, this condition lasts until the spell ends or dispel magic is cast on the character.

Countermeasures. A successful DC 15 Wisdom (Perception) check reveals the presence of the pressure plate on the pedestal. The pressure plate can be neutralized, and the helmet removed if a character quickly swaps an item of equal weight with the helmet, placing that item on the pressure plate. The character must make a successful DC 15 Intelligence (Investigation) check to determine the weight of the helmet (twelve pounds). Then the character must make a successful DC 13 Dexterity (Sleight of Hand) check to swap the helmet with the item without tripping the pressure plate. If either of these checks fail, the trap is triggered.

Stairway to Slime CR 5-10

Source Trap Collection by TheDMLair. Author Luke Hart

Simple Mechanical Trap

Description. There is a ladder that must be climbed to get to the next level up.

Trigger. The sixth rung on the ladder pulls loose when climbed on and triggers the trap.

Effect. Triggering the trap causes a trap door in the floor to slide open, revealing a ten-foot-deep pit whose floor and walls are covered with green slime (see the game master’s core rulebook). The character who pulled the rung loose on the ladder must make a DC 14 Dexterity saving throw or fall into the pit. The character takes 1d6 falling damage and is covered with green slime, taking 5 (1d10 acid damage). The creature takes the damage again at the start of each of its turns until the slime is scraped off or destroyed. Against wood or metal, green slime deals 11 (2d10) acid damage each round, and any nonmagical wood or metal weapon or tool used to scrape off the slime is effectively destroyed.

Countermeasures. A successful DC 14 Wisdom (Perception) check reveals that one of the ladder rungs is loose.

Dart Trap CR 1—2

Simple Mechanical Trap

Appearance Several concealed holes adorn both sides of a room or corridor, with so many openings spread across that it’s impossible to pass without being in front of at least a few of them.

Trigger A creature or object weighing more than 20 pounds steps or lands on the pressure plate that activates the trap.

Detection A successful DC 15 Wisdom (Perception) check reveals the holes in the wall and the presence of a trap, but a separate DC 15 Intelligence (Investigation) check is required to reveal where the pressure plate is.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools disables the lever (if the person attempting it can reach the lever) or the pressure plate.

Damage and Effects When triggered, the Dart Trap fires 4 darts.

Each dart makes a ranged attack with a +8 bonus. These darts target a random creature within 10 feet of the pressure plate. Each creature that is hit takes 2 (1d4) piercing damage.

Some of these traps are poisoned (adding 1 to the CR), in which case any creature hit must succeed on a DC 15 Constitution saving throw, taking 11 (2d10) poison damage on a failed save, or half as much damage on a successful one.

Divide and Conquer CR 1

Simple Mechanical Trap

Appearance An empty room with a 6-inch deep and 12 inches wide trench dividing the room into two equal sizes, with two doors leading out of the room, diametrically across from each other.

Trigger A minimum of two creatures enter the room and are separated on each side of the room.

Detection A successful DC 11 Wisdom (Perception) check reveals the trap.

Disarming or Destroying A successful DC 11 Dexterity check using thieves’ tools disables it by jamming the wall mechanics. The trap cannot be destroyed, but the wall that slides down can. It has an AC of 17 and 50 hit points. The doors leading out on either side have an AC of 15 and 30 hit points, as they are steel-reinforced.

Damage and Effects When triggered, both doors close, and a wall slowly descends from the roof, separating the room into two. It does this slowly enough that anyone on one side can make it to another without issue.

On the wall is a lock. The lock unlocks the door on the other side of the room, and can be picked with a successful DC 12 Dexterity check using thieves’ tools. There is no other way of opening the doors on either side (i.e. to open the one on the left side, you must pick the lock on the right side, and vice versa). The doors can be opened from the outside of the room as normal, though they are locked. They can still be picked as normal.

The trap resets when the doors are opened at the same time.

GM’s Note: This trap is deliberately designed to slow down or restrain the heroes from going anywhere. Not all trap-makers want to kill people.

Elevator Room CR 1

Simple Mechanical Trap

Appearance An empty room with 4 doors, one on each wall.

Trigger A minimum of one creature enters the room and spends 1 round in the room.

Detection A successful DC 12 Wisdom (Perception) check reveals the trap.

Disarming or Destroying A successful DC 12 Dexterity check using thieves’ tools disables it by jamming the elevator mechanics. The doors can be destroyed. Each has an AC of 17 and 20 hit points. They can also be forced open with a DC 20 Strength (Athletics) check.

Damage and Effects When triggered, any open doors close 1round later, to trap as many people as possible.

Once the doors close, they lock and the room descends, one level (or 20 feet) per round. This continues until the Elevator Room reaches the bottom at which time the doors open.

GM’s Note: This trap is deliberately designed to bring creatures in over their heads and is only used in dungeons and other areas where there is a significant increase in danger the further one goes. As such, it is not unusual to find these in the lairs of liches and dragons, who often find that those caught in such a simple trap make for easy fodder.

Falling Net CR 1

Simple Mechanical Trap

Appearance A net is suspended from above, with a tripwire activating the trap, capturing those caught beneath it.

Trigger When a creature moves the tripwire the trap triggers.

Detection A successful DC 10 Wisdom (Perception) reveals the tripwire and the net.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools breaks the tripwire harmlessly.

Anyone with an edged weapon or tool can attempt the check, but they have disadvantage when doing so. Failing the check triggers the trap.

Damage and Effects When the trap is triggered, the net releases, covering a 10-foot-by-10-foot area.

Those within that area are restrained and those that fail a DC 10 Strength saving throw are knocked prone.

A creature can free itself (or any creature in range) by using an action to make a DC 10 Strength (Athletics) check and succeeding.

The net has AC 10 and 20 hit points, and for each 5 slashing damage dealt, a 5-foot square section is destroyed, which frees any creatures trapped in that section.

GM’s Note: An alternate version of this has the net spread on the ground, and when triggered, pulls the creatures in the area into the air, suspending them from above, at least 20 feet up. This works similarly to the falling net, but any creatures who free themselves (or where the net is destroyed) fall to the ground taking 7 (2d6) bludgeoning damage (this increases the CR of the trap to 2).

Falling Wasp Nest CR 1

Simple Mechanical Trap

Appearance A small wire or string is stretched across the ground, set to trip anyone crossing it. Once tripped, a wasp nest falls from a perch above, pulled down by the string, breaking it open and unleashing the angry wasps.

Trigger A creature triggers the wire.

Detection A successful DC 12 Wisdom (Perception) check reveals the trap.

Disarming or Destroying A successful DC 10 Dexterity check using thieves’ tools disables it. The trap can be destroyed by dealing 1 point of damage to it. It has an AC of 12.

Damage and Effects The trap drops a wasp nest from at least 10 feet above, breaking it open upon impact with the ground. The wasps immediately stream out and sting anyone within a 10 foot radius.

Anyone within a 10 foot radius must make a DC 10 Dexterity saving throw. On a failed save, a creature takes 3 (1d6) piercing damage, or half as much on a successful one. The wasps remain in the area for 1 minute, attacking anyone who comes into the radius. After 1 minute they disperse automatically.

Ladder To Nowhere CR 1

Simple Mechanical Trap

Appearance A square trapdoor with 2-½-foot long sides in a scuffed wooden floor reveals a metal ladder that descends to an unlit room below. The ladder is bolted to the wall of the room below.

Trigger A lever disguised to look like a ladder rung is located 50 feet down the 70-foot long ladder.

When five pounds of pressure is applied to the rung, it triggers a mechanism hidden behind the wall that releases a block of stone concealed in the ceiling in the room above.

Detection If a creature examines the ceiling, a successful DC 15 Wisdom (Perception) check reveals the seams of a square outline with 3-foot long sides. If a creature examines the ladder as they descend it, a successful DC 15 Wisdom (Perception) check reveals the false ladder rung.

Disarming or Destroying A successful DC 5 Dexterity check allows a creature to avoid the ladder rung that triggers the trap. A successful DC 10 Dexterity check using thieves’ tools disarms the trap as the hero stabilizes the false rung.

Damage and Effects When the lever activates, a 3-foot long by 3-foot wide by 6 inches thick cut-out section of the stone ceiling in the top room is released and lands over the trapdoor sealing off the room’s only exit. The stone slab weighs 800 pounds, which can be pushed, dragged, or lifted as normal.

Pit Trap CR 1—5

Simple Mechanical Trap

GM’s Note: Pit Traps are generally put into three categories: Standard (CR 1), Hidden (CR 2), and Locking (CR 3). Any of these can have spikes and other nasty effects added to them (Adding 1 to the CR). Finally, a spiked pit can have an injury poison on the spikes (which adds a further 1 to the CR for a total of 2 for spikes and poison).

Appearance A hole in the ground hidden beneath a carpet, blanket, or similar material that hides the opening. The hole drops down at least 10 feet.

Trigger A creature steps on the covering material.

Detection Standard: A successful DC 10 Wisdom (Perception) check reveals the trap.

Hidden: A successful DC 15 Wisdom (Perception) check reveals the trap as the hero discerns the lack of traffic across that section of ground. For the hidden pit, it is always a trapdoor that covers the hole, making it blend almost seamlessly with the ground.

Locking: A locking pit is similar to a hidden pit for detection purposes.

Disarming or Destroying Standard: A standard pit trap cannot be disarmed, and destroying it is a simple matter of filling the hole with dirt or some other material.

Hidden: The trapdoor of a hidden pit can be disabled with a DC 11 Dexterity check using thieves’ tools to jam the trapdoor, preventing it from opening. The trapdoor can also be destroyed. The AC and hit points depend on its material, but in most dungeons, it is made of stone and has an AC of 17 and 20 hit points.

Locking: The trapdoor of a locking pit functions like the trapdoor of a hidden pit, but opening the lock requires a DC 15 Dexterity check using thieves’ tools if the trap has already been triggered (before this point, it can be disabled like a hidden pit). It has the same AC and hit points as a hidden pit, but the trapdoor can be pried open with a successful DC 20 Strength (Athletics) check.

Damage and Effects All pits deal damage to those who fall into them, depending on the depth. For every 10 feet deep that the pit is, it deals 3 (1d6) bludgeoning damage (Up to a maximum of 20d6). Most pits are between 10 and 20 feet deep.

Spiked pits have sharpened stakes at the bottom of the pit, often made from wooden stakes or iron spikes. These deal an additional 11 (2d10) piercing damage on top of the falling damage.

Finally, some of the spiked traps have poison smeared on them. This can be any poison of the creator’s choice, but the most typical one requires a DC 13 Constitution saving throw, taking 22 (4d10) poison damage on a failed save, or half as much damage on a successful one.

Ankle Chopper CR 2

Simple Mechanical Trap

Appearance A set of wooden stairs leads up to an open door.

Trigger When stepped on, the tread halfway up the staircase is a pressure plate that pulls the panel on the step’s riser down.

Detection If a creature examines the step, a successful DC 10 Wisdom (Perception) check reveals a different sound behind the trapped riser.

Disarming or Destroying A successful DC 5 Dexterity check allows a creature to skip the trapped step to avoid triggering the trap. A DC 10 Dexterity check using thieves’ tools will successfully support the pressure plate to keep it from depressing and prevent the trap from tripping.

Damage and Effects A handaxe springs out from under the stair and strikes the shin of the creature that stepped on the pressure plate dealing 1d6 + 1 point of slashing damage. Simultaneously, grease is released that flows down the stairs.

Each creature on the staircase must make a successful DC 11 Dexterity save or slip and tumble down to the base of the stairs taking the appropriate amount of damage for the distance fallen.

Bear Trap CR 2

Simple Mechanical Trap

Appearance A set of iron jaws, in the form of a bear trap, are set upon the ground and covered.

Trigger A creature steps on the bear trap.

Detection A successful DC 10 Wisdom (Perception) check reveals the trap.

Disarming or Destroying A successful DC 10 Dexterity check using thieves’ tools disables it. The trap can be destroyed by dealing 5 points of damage to it. It has an AC of 12.

Damage and Effects The trap makes an attack against the triggering creature. The attack has a +8 attack bonus and deals 5 (1d10) piercing damage on a hit. This attack can’t gain advantage or disadvantage. A creature hit by the trap has its speed reduced to 0. It can’t move until it breaks free of the trap, which requires a successful DC 15 Strength check by the creature or another creature adjacent to the trap.

Crushing Door CR 2

Simple Mechanical Trap

Appearance A closed wooden door.

Trigger Turning the door handle.

Detection A successful DC 10 Wisdom (Perception) check reveals deteriorated hinges and no airflow coming from under the crack of the door.

GM’s Note: There’s no airflow because it’s a false door. There is no room behind the door, only a wall.

Disarming or Destroying A successful DC 10 Dexterity check using thieves’ tools jambs the mechanism in the handle so it can’t release acid onto the hinges.

Damage and Effects Acid coats the hinges causing them to dissolve which releases the door that falls forward onto the creature that triggered the trap. The creature must make a DC 10 Dexterity saving throw. On a failed save, the creature takes 11 (2d10) bludgeoning damage and is pinned under the door, or half as much damage on a successful save. A creature is not pinned on a successful save. Every round a creature starts its turn pinned under the door, it takes 1d6 points of bludgeoning damage. A creature can use its action to push the door off a pinned creature with a successful DC 15 Strength (Athletics) check.

Seat of Entrapment CR 2

Simple Mechanical Trap

Appearance An ornate, stone throne sized for an adult humanoid with a coin-sized ruby embedded on each of its arms.

Trigger Sitting on the throne with at least 50 pounds of weight releases a concealed catch underneath the seat that is holding the stone arms in place.

Detection A successful DC 10 Wisdom (Perception) or Intelligence (Investigation) reveals the concealed catch under the seat and the sliver of a groove where the hinges are located at the spots where the arms and the back of the chair meet.

Disarming or Destroying A successful DC 10 Dexterity check using thieves’ tools to block the catch from releasing will prevent the trap from tripping. If the trap is tripped, a creature that is not pinned in the throne can make a successful DC 12 Strength (Athletics) check to manually reset the catch under the seat which will release the arms and reset them to their original open position.

A creature pinned in the chair can make a successful DC 12 Dexterity (Acrobatics) check to wriggle free from the arms. A creature larger than Medium makes the check at disadvantage.

Damage and Effects When the trap triggers, a creature sitting on the throne can make a DC 12 Dexterity saving throw to leave the throne before the released arms come together to entrap the creature on the throne. A creature sitting on the throne when the arms come together takes 11 (2d10) points of bludgeoning damage and gains the restrained condition.

Corpse Box CR 3

Simple Mechanical combination trap

Appearance An ornate stone coffin decorated with images of people being trapped alive inside it.

Trigger A creature opens the trap.

Detection A successful DC 14 Wisdom (Perception) check reveals the trap. Detect magic reveals an aura of conjuration magic emanating from inside the coffin.

Disarming or Destroying The Corpse Box cannot be disabled through mechanical means, though it can be opened after it has triggered with a successful DC 14 Dexterity check using thieves’ tools. The trap can be destroyed by dealing 15 points of damage to it. It has an AC of 16. This destroys the lid, and if there is a trapped occupant, they can escape.

Damage and Effects As tentacles emerge, the trap makes an attack against the triggering creature. The attack has a +5 attack bonus and deals 5 (1d10) bludgeoning damage and the target is grappled (escape DC 17). Until this grapple ends, the creature is restrained.

The target is then dragged into the coffin which slams shut revealing that it is lined with spikes, which pierce the trapped occupant.

This automatically causes 10 (2d10) piercing damage on each round that the creature is trapped.

Once the occupant is dead, the trap opens and the corpse is expelled. This resets the trap.

Deterring Door CR 3

Simple Magic Mechanical Trap

Appearance An immobile door with no obvious knob or lock has an intricate brass knocker on it in the form of a jester’s head.

Trigger A creature that uses the knocker triggers the trap.

Detection A successful DC 15 Wisdom (Perception) check or DC 15 Intelligence (Arcana) check reveals an arcane symbol on the underside of the door knocker incorporated into its elaborate design. Detect magic reveals abjuration and enchantment auras on the door.

Disarming or Destroying Dispel magic (DC 12) will dispel the enchantment magic and the arcane lock on the door.

Damage and Effects The arcane lock spell doesn’t deal damage to nearby creatures, but it does keep them from entering unless they employ a knock spell or physically destroy the door.

After a creature uses the door knocker, they hear the following words (in Common) in their mind: “Travel as far away from here as you possibly can.” If the creature doesn’t understand common or can’t be charmed, it is immune to the effects. Otherwise, it must make a DC 12 Wisdom saving throw. On a failed save, the creature must comply with the request to the best of its ability for the next hour.

Hall of Mirrors CR 3

Simple Magic Mechanical Trap

Appearance A hallway (25-feet long & 5-feet wide) with an arch at both ends has several paintings, ornate mirrors, and clay busts lining the walls. A thin red carpet runs down the center of the hall. A carved lion’s head adorns the top of the first arch. When a creature approaches within 5-feet of the lion’s head, a magic mouth spell activates and the lion says, “speak the password or go no further”.

Trigger A creature passes under the exit arch without having said “the password” aloud.

Detection Detect magic on the second arch reveals an aura of evocation magic. A successful DC 15 Intelligence (Investigation) or Intelligence (Arcana) check reveals a glyph inscribed on the underside of the exit arch.

Disarming or Destroying Dispel magic (DC 12) dispels the glyph. A successful DC 15 Intelligence (Arcana) ability check also destroys the glyph as the hero disrupts the magic pattern of the glyph.

Detect magic reveals an aura of illusion magic centered on the sigil.

Damage and Effects As the glyph triggers, it releases a shatter spell.

All creatures within 10 feet of the exit arch must make a DC 12 Constitution saving throw.

A creature takes 13 (3d8) thunder damage on a failed save, or half as much on a successful save. Simultaneously, the mirrors shatter and send flying glass shards into the hallway.

All creatures within 10 feet of the exit arch must make a DC 15 Dexterity saving throw. A creature takes 13 (3d8) slashing and piercing damage on a failed save, or half as much on a successful save.

Lure of Greed CR 3

Simple Mechanical Trap

Appearance A backpack, sack, or chest that has been badly hidden.

Trigger A creature opens or moves the container.

Detection A successful DC 13 Wisdom (Perception) check reveals the trap.

Disarming or Destroying A successful DC 15 Dexterity check disables it. Failing the check triggers the trap. The trap cannot be destroyed without destroying the container.

Damage and Effects The trap unleashes a cloud of poison in a cone 10 feet long, centered on the container, in the direction of the creature opening it. All creatures within the cone must make a DC 12 Constitution saving throw. On a failed save, it takes 6 (1d12) poison damage and is poisoned for 24 hours. On a successful save, the creature takes half damage and isn’t poisoned.

The container may or may not be full at the GM’s discretion, but it is likely empty as it was badly hidden on purpose to tempt would-be thieves into disturbing it.

Needle Trap CR 3

Simple Mechanical Trap

Appearance A chest or door, or similar object that a creature would want to open.

Trigger The object is opened, triggering the trap.

Detection A successful DC 20 Intelligence (Investigation) check reveals the presence of the trap, as alterations are made to the locking mechanism of the object. Casual inspection, such as with a Wisdom (Perception) check, is not enough to reveal the presence of the trap.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools disarms the trap, allowing the object to be opened safely. Failure triggers the trap.

Damage and Effects When the trap is triggered a needle extends 3 inches straight out from the lock, damaging the creature manipulating the object. That creature takes 1 piercing damage and 11 (2d10) poison damage and must succeed on a DC 15 Constitution saving throw or be poisoned for 1 hour.

Punji Sticks CR 3

Simple Mechanical Trap

Appearance Several sharpened sticks, usually smeared with sewage or other diseased filth, strike from tension, impaling a victim.

Trigger When a creature moves the tripwire the trap triggers.

Detection A successful DC 15 Wisdom (Perception) check reveals the tripwire.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools cuts or disables the trip wire safely (the person making the check can reset the trap if they wish). Anyone with an edged weapon or tool can attempt the check, but they have disadvantage when doing so. Failing the check triggers the trap.

Damage and Effects When triggered, the punji sticks strike out, attacking the triggering creature. The sticks make a single melee attack with a +8 bonus.

The triggering creature takes 6 (3d4) piercing damage if they are hit.

They must also make a DC 10 Constitution saving throw or contract a nasty disease. If they fail the saving throw, they become poisoned until the disease is cured. For every 24 hours that elapse, the target must repeat the saving throw, reducing its hit point maximum by 2 (1d4) on a failure. The disease is cured on a success. The target dies if the disease reduces its hit point maximum to 0. This reduction to the target’s hit point maximum lasts until the disease is cured.

This trap must be manually reset.

Rope Bridge Trap CR 3

Simple Mechanical Trap

Appearance A rickety bridge crosses a large chasm.

Trigger When more than two Medium-sized creatures step on the bridge, it collapses, or it is activated by a creature cutting one of the ropes.

Detection A successful DC 12 Wisdom (Perception) reveals that the bridge is unstable and could collapse if too much weight is put on it.

Disarming or Destroying The trap cannot be disarmed. Destroying it is a simple matter of cutting the ropes, which have an AC of 5 and 2 hit points. This drops any creatures currently on the bridge into the chasm below.

Damage and Effects When activated, the triggering creatures are dropped to the chasm below unless they succeed on a DC 17 Dexterity saving throw.

Each creature takes falling damage from the drop (typically this drop is at least 50 feet, meaning they take 17 (5d6) bludgeoning damage). Some trapmakers fill the chasm below with spikes like a pit trap. These deal an additional 11 (2d10) piercing damage on top of the falling damage. (and increases the CR by 1) Finally, some of the spikes may have poison smeared on them. This can be any poison of the creator’s choice, but the most typical one requires a DC 13 Constitution saving throw, taking 22 (4d10) poison damage on a failed save, or half as much damage on a successful one. (which increases the CR by a further 2, to a total of 6).

Sewer Pit CR 3—4

Simple Mechanical Trap

Appearance A trap door drops the heroes into a pit. The door then closes and the pit trap fills with sewage.

Trigger A creature steps on the trap door.

Detection A successful DC 12 Wisdom (Perception) check reveals the trap.

Disarming or Destroying A successful DC 12 Dexterity check using thieves’ tools disables it by jamming the trap door closed. The trap door can be destroyed (AC 14 and 15 hit points), but this only leaves the pit open and creatures can still fall into it.

Damage and Effects Any creature that falls into the 30-foot deep pit takes 3d6 bludgeoning damage from the fall.

Immediately thereafter the cover closes, and the pit begins to fill with a mix of sewage and water.

After 2 rounds the pit is filled, and the creature must hold its breath or begin drowning.

They must also make a DC 10 Constitution saving throw or contract a nasty disease. If they fail the saving throw, they become poisoned until the disease is cured. Every 24 hours that elapse, the target must repeat the saving throw, reducing its hit point maximum by 2 (1d4) on a failure. The disease is cured on a success. The target dies if the disease reduces its hit point maximum to 0. This reduction to the target’s hit point maximum lasts until the disease is cured.

A successful DC 20 Strength (Athletics) check is necessary to pry the cover open. The cover can also be smashed open. A character in the pit can also attempt to disable the spring mechanism from the inside with a DC 15 Dexterity check using thieves’ tools, provided that the mechanism can be reached and the character can see. In some cases, a mechanism (usually hidden behind a secret door nearby) opens the pit.

GM’s Note: Some of these only fill with normal water, drowning the triggering creature. These are CR 3.

Smoke & Arrows CR 3

Simple Mechanical Trap

Appearance A 15-feet-by-15-feet torch-lit foyer has two wooden statues armed with light crossbows.

The statues stand on opposite walls 5 feet into the room.

Trigger A trip wire stretched between the two statues causes the crossbows to fire.

Additionally, a pressure plate is located directly in front of the exit door at the other end of the foyer.

Detection A DC 5 Wisdom (Perception) check reveals that the crossbows are functioning.

GM’s Note: This is the “red herring”. The heroes are supposed to discover this part of the trap, to lure them into missing the second one.

A successful DC 8 Wisdom (Perception) check reveals the trip wire.

A successful DC 15 Wisdom (Perception) check reveals all of the following: the pressure plate, the secret compartment on the wall behind the lit torch at the exit door, and a scorch mark on the wall near the torch.

Disarming or Destroying A successful DC 13 Dexterity check using thieves’ tools allows a creature to snip the trip wire without triggering the first part of the trap.

The crossbows can be removed and used as functioning weapons.

A successful DC 13 Dexterity check using thieves’ tools will prevent either the pressure plate or the secret compartment from functioning as the hero jams them in place.

Damage and Effects One crossbow bolt from each statue attacks the creature activating the trip wire. Each bolt makes a ranged attack with a +8 bonus, and deals 1d8 piercing damage.

As the pressure plate depresses, a secret compartment on the wall behind the lit torch slides open, and oil is sprayed onto the torches causing a burst of fire to flare up in a 5-foot radius. Creatures in the radius must make a DC 12 Dexterity saving throw. On a failed save, the creature takes 12 (2d10) fire damage, or half as much on a successful save.

Stairway to Pain CR 4

Simple Mechanical Trap

Appearance A set of wooden stairs leading up at a steep angle, at least 20 feet long.

Trigger A creature steps on the second step from the top.

Detection A successful DC 13 Wisdom (Perception) check reveals the trap.

Disarming or Destroying A successful DC 12 Dexterity check using thieves’ tools disables it. The trap can be destroyed by damaging the triggering step. This step has an AC of 8 and 10 hits points. If it is not destroyed in a single successful hit, it will activate the trap.

Damage and Effects When a creature steps on the “trigger step”, which is the second step from the top, the trap activates and every step on the stairs rotates and reveals razor-sharp blades mounted on them. Each step is now at an angle causing every creature to slide down the stairs, taking damage from each individual set of blades. The amount of damage varies by creature position.

Creatures in the bottom 5 feet of the stairs take no damage as they jump off the stairs.

Creatures above take 3 (1d6) slashing damage per 5 feet that they slide down and do not ignore the last 5 feet (on a typical set of stairs, that is 12 (4d6) slashing damage for sliding 20 feet down). The creatures must make a DC 12 Dexterity saving throw taking full damage on a failed save, or half as much damage on a successful one.

As soon as there are no more creatures on the stairs, the trap resets.

Dead Herring CR 4

Simple Mechanical Trap

Appearance A corpse lies rotting on the floor. At first glance, it appears to be garbed in fine quality clothing and the hilt of a long sword sticks out from underneath the body.

Trigger Jostling the body to loot or move it causes the dagger concealed under the body to slice open the bladder, releasing the poison.

Detection A successful DC 15 Wisdom (Perception) check notices the unusual angle at which the body is resting — almost as though it is posed.

Disarming or Destroying A successful DC 13 Dexterity check disarms the trap as the hero prevents the alchemical reagents from mixing. Anyone using alchemist’s supplies to disarm the trap gains advantage on the check.

Damage and Effects When the liquid alchemical component seeps from its container, it mixes with the powdered alchemical component on the floor below it and produces poisonous gas fumes. All creatures within a 15-foot-radius of the corpse must make a DC 13 Constitution saving throw.

On a failed save, the creature takes 16 (4d6) poison damage and is poisoned for 1 hour. On a successful save, the creature takes half as much damage and is not poisoned.

Sandwiched In Stone CR 4

Simple Mechanical Trap

Appearance An unlit 10-foot long by 5-foot wide underground hallway with a closed door at the end. The walls and floor of this hallway are made of rough, unworked stone. The unworked nature of the floor results in uneven areas of elevation and occasional small rocks dotting the path— the floor is difficult terrain.

Trigger Touching and turning the unlocked door’s handle.

Detection A successful DC 10 Wisdom (Perception) check reveals the slight smell of rotting garbage tinged with sulfuric acid typical of crawler mucus coming from the door handle. Additionally, a successful DC 13 Wisdom (Perception) check reveals thin tracks embedded in the natural stone ceiling and floor that run from both sides of the walls into the center of the room.

Disarming or Destroying A successful DC 10 Dexterity check allows a creature to wipe the carrion crawler mucus off the door handle without poisoning itself. A successful DC 15 Dexterity check using thieves’ tools allows the hero to jamb the tracks to keep the crushing stones at bay.

Damage and Effects A creature subjected to the poison must succeed on a DC 13 Constitution saving throw or be poisoned for 1 minute. The poisoned creature is paralyzed. The creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

As the door handle turns, 2-foot sections of wall (one on each side of the hall) slide along the tracks and slam together in the center of the hallway, crushing any creature standing in front of the door before retracting and resuming their original position. A mobile (non-paralyzed) creature that is standing in front of the door when this occurs can make a DC 10 Dexterity saving throw. The creature takes 22 (4d10) bludgeoning damage on a failed save, or half as much on a successful save.

Bard’s Bane CR 5

Simple Mechanical Trap

Appearance A finely crafted harp.

Trigger One string is off-key, and when its hollowedout tuning head is turned, the poison dust stored within is released.

Detection Because the poison dust is minuscule in size and weight and it is concealed within the tuning head, it is very difficult to detect.

A successful DC 20 Wisdom (Perception) or Intelligence (Investigation) check reveals a pinsized hole in the tuning head.

Disarming or Destroying A successful DC 10 Dexterity check using thieves’ tools will plug the hole and keep the dust from contaminating the harp.

Damage and Effects Once the trap is triggered, a few particles of poison dust (invisible to the naked eye) trickle down and coat the out-of-tune string. The poison remains potent until it is absorbed by contact with skin. When the string is plucked, the player of the harp must make a DC 15 Constitution saving throw. On a successful save, the creature takes 22 (4d10) necrotic damage or half as much on a failed save. The tuning head holds one dose of poison.

Spear Trap CR 5 — 6

Simple Mechanical Trap

Appearance Two lattice works made from spears spring from either side of a corridor when a beam of light is crossed.

Trigger A creature or object that’s Small or bigger passed through a beam of light.

Detection A successful DC 13 Wisdom (Perception) check reveals the presence of the trap, and that it’s activated by moving through the beam of light.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools disarms the trap. Anyone without thieves’ tools can attempt to disarm the trap, but they have disadvantage when doing so.

Failing the check triggers the trap.

Damage and Effects When triggered, the spears shoot out from either side, with 5 (1d10) spears attacking the triggering creature. Each spear makes a melee attack with a +8 bonus. The triggering creature takes 4 (1d8) piercing damage from each spear that hits.

Some of these traps are poisoned (adding 1 to the CR), in which case any creature hit must succeed on a DC 15 Constitution saving throw, taking 11 (2d10) poison damage on a failed save, or half as much damage on a successful one.

The trap resets on the following round.

GM’s Note: This is the trap you see on the front of this book.

Suffocating Room CR 5

Simple Mechanical Trap

Appearance An underground complex where the rooms are carved into the stone. The door to a 15-foot square library stands open. A rocking chair, a bearskin rug, and a pedestal with a pipe, a pewter goblet, and an empty glass decanter resting upon it occupy the center of the room.

The walls to the right and left and opposite the door are covered from floor to ceiling with bookcases packed with books.

Trigger When the heavy pewter chalice is moved, the switch that it depresses will pop up and trigger the air removal trap sequence.

Detection A successful DC 15 Wisdom (Perception) or Intelligence (Investigation) check reveals scuff marks on the floor just inside the room’s threshold in front of the door. If a creature examines the bookcase behind the books, a successful DC 15 Intelligence (Investigation) check reveals numerous pinhead-sized holes bored into the wooden bookcase that continue through the stone wall behind it.

Disarming or Destroying A successful DC 15 Dexterity check allows a creature to substitute an appropriately weighted object for the chalice so that the switch remains depressed, keeping the trap from triggering. Alternatively, a successful DC 10 Dexterity check using thieves’ tools made in conjunction with a DC 15 Intelligence (Investigation) check to find and plug all of the tiny holes will keep the air from being sucked out of the room.

Damage and Effects As the trigger switch activates, a panel of the stone wall to the left of the door slides in front of the door making an airtight seal and the mechanisms hidden within the walls simultaneously suck the air from the room. It takes 1 minute before all the air is sucked from the room. At that time, creatures in the room are subject to suffocation.

A creature can hold its breath for a number of minutes equal to 1 + its Constitution modifier (minimum of 30 seconds). When a creature runs out of breath, it can survive for a number of rounds equal to its Constitution modifier (minimum of 1 round). At the start of its next turn, it drops to 0 hit points and is dying, and it can’t regain hit points or be stabilized until it can breathe again.

The stone panel barring the exit has an AC 17 and 510 hit points. It has immunity to cold, fire, poison, psychic, radiant, slashing, and thunder damage and resistance to necrotic damage.

Swinging Blades CR 5

Simple Mechanical Trap

Appearance Large blades, shaped like crescent axes, swing like pendulums across a corridor, cutting any creatures caught in it to shreds.

Trigger Activated by pulling a lever or by stepping on a pressure plate in the middle of the area of effect, attacking any creatures in an area 10 feet ahead and behind the activating creature.

Detection A successful DC 15 Wisdom (Perception) check reveals the location of the lever, which is normally somewhat out of sight (but normally within 100 feet) of the pressure plate.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools disables the lever (if the person attempting it can reach the lever) or the pressure plate.

Damage and Effects All Medium or larger creatures within a 5-footwide and 20-foot-long area must make a DC 15 Dexterity saving throw or take 14 (4d6) slashing damage on a failed save, or half as much damage on a successful one. The damage continues each round following activation unless the trap is turned off or disabled.

If triggered by the pressure plate, the area of effect is centered on the pressure plate itself.

Camouflaged Pit Trap

Simple Mechanical Trap

Source DiFP

This pit has a cover constructed to resemble the floor around it. When a creature steps on the cover, it swings open causing the intruder to spill into the pit below, a ten foot fall that inflicts 1d6 bludgeoning damage.

A successful DC 15 Wisdom (Perception) check discerns the strange lack of foot traffic over the section of the floor and discovers the trap. Once discovered, it can only be disarmed by using something to wedge the trapdoor in such a way that prevents it from opening, whether a simple iron spike hammered between door and floor, or the use of arcane lock or similar magics.

Dumbwaiter Disaster CR 6

Simple Mechanical Trap

Appearance A set of muddy footprints belonging to a barefoot humanoid leads up and into a dumbwaiter but the dumbwaiter is currently empty. The dumbwaiter is large enough to accommodate a Small creature and the ropes for operating it on either side are intact.

Trigger Raising the two-story dumbwaiter.

Detection A successful DC 20 Wisdom (Perception) check reveals the remnants of a fine dust below the dumbwaiter where the base of the wall and the floor meet. The mechanism that houses and triggers the trap is behind the dumbwaiter box in the shaft and can’t be inspected by normal means while the dumbwaiter is on the first floor.

There is a 1-inch gap between the inner box and the outer wall of the shaft that would allow something minuscule to fit through such as an arcane eye. This strategy would allow the caster to look behind the inner box of the dumbwaiter and see the hook and the outline of the sliding door in the shaft that contains the hammer.

Disarming or Destroying When the inner box housing of the dumbwaiter is raised, a hook on the back of the box lifts a panel in the shaft that releases a spring-loaded hammer attached to a vial of blinding dust.

When the hammer slams down onto the shelf at the base of the dumbwaiter, the vial explodes, dispersing the blinding powder into the 5-foot space adjacent to the dumbwaiter. A successful DC 15 Dexterity check using thieves’ tools allows a creature to deconstruct the inner box housing of the dumbwaiter. Failing to disarm the trap triggers it.

Damage and Effects Any creatures in the 5-foot square adjacent to the dumbwaiter opening when the vial of blinding powder shatters must make a DC 13 Dexterity saving throw. A creature gains the blinded condition for 1 hour and takes 22 (4d10) slashing and piercing damage from tiny slivers of glass and chalk dust that coat their eyes and throat on a failed save. On a successful save, a creature takes half as much damage and is not blinded.

Roof Collapse CR 6

Simple Mechanical Trap

Appearance An unstable section of the ceiling is held up with rudimentary supports.

Trigger A creature moves a tripwire stretched across the ground between two support beams that are set very loosely, dislodging them.

Detection A successful DC 10 Wisdom (Perception) reveals the tripwire.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools cuts or disables the trip wire safely (the person making the check can reset the trap if they wish). Anyone with an edged weapon or tool can attempt the check, but they have disadvantage when doing so. Failing the check triggers the trap.

Damage and Effects When triggered, the ceiling collapses and any creature in the area (typically a 20-foot deep area that’s as wide as the room or corridor) beneath the unstable ceiling must attempt a DC 15 Dexterity saving throw, taking 22 (4d10) bludgeoning damage on a failed save, or half as much damage on a successful one. Once the trap is triggered, the floor of the area is filled with rubble and becomes difficult terrain.

GM’s note: Some of these traps drop far more debris than normal, as they are intended to collapse the tunnel, blocking off any entry completely. These traps deal 44 (8d10) bludgeoning damage on a failed save, or half as much on a successful one. When triggered, the area under the collapsed ceiling becomes impassable terrain. This version of the trap has a CR of 8.

This particular trap can also be used to simulate natural hazards such as mineshaft cave-ins or tumbling rocks on a mountainside.

Rust Dust CR 7

Simple Mechanical Trap

Appearance An underground cavern.

Trigger A trip wire strung between two boulders is rigged to release a net overhead.

Detection A successful DC 15 Wisdom (Perception) check reveals the trip wire and the net.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools disables the trip wire without causing the net to drop.

Damage and Effects The net is coated with rust dust and covers a 10-foot-by-10-foot area centered on the trip wire. Any creature within this area must succeed on a DC 15 Dexterity saving throw or be restrained.

Rust dust affected any nonmagical ferrous metal items worn or carried such as armor, shields, weapons, etc, automatically suffer a penalty at the start of every round that a creature is restrained in the net. Armor and shields suffer a permanent and cumulative -1 penalty to the AC they provide. Armor reduced to an AC of 10 is destroyed. A shield that drops to a +0 bonus is destroyed. Weapons take a permanent and cumulative -1 penalty to damage rolls. If a weapon’s penalty drops to -5, the weapon is destroyed.

Using an action to make a DC 10 Strength (Athletics) check successfully frees a creature from the net. Dealing at least 5 points of slashing damage (AC 10) to the net where it is in contact with a creature, frees the creature, though a metal weapon used for this purpose suffers the -1 penalty even if it’s being used by a creature outside of the net.

Rolling Boulder CR 10

Simple Mechanical Trap

Appearance A narrow tunnel, just over 10 feet wide, with a trapdoor in the ceiling from which rolls a 10- foot diameter boulder, crushing everything in its path.

Trigger When more than 20 pounds of weight is placed on the pressure plate.

Detection A successful DC 15 Wisdom (Perception) check reveals the pressure plate and the trapdoor in the ceiling or the streaks on the walls or floor where the boulder has passed by previously.

Disarming or Destroying Disarming the trap can be done by jamming a spike under the pressure plate or similar.

This can be done with a DC 15 Dexterity check. If using thieves’ tools or you have the Stonecunning racial ability, you gain advantage on the check. If it fails, you automatically trigger the trap.

Damage and Effects When activated every creature in the path of the boulder must make an Initiative check. The boulder rolls initiative with a +8 bonus, and on its turn it moves 60 feet in a straight line away from the trapdoor. The boulder can move through creatures’ spaces, and creatures can move through its space, treating it as difficult terrain.

Whenever the boulder enters a creature’s space or a creature enters its space while it’s rolling, that creature must succeed on a DC 15 Dexterity saving throw or take 55 (10d10) bludgeoning damage and be knocked prone.

The boulder stops when it hits a wall or similar barrier and cannot go around corners, but it can do gentle curving turns if the walls are built to guide such movement.

As an action, a creature within 5 feet of the boulder can attempt to slow it down with a DC 20 Strength (Athletics) check. On a successful check, the boulder’s speed is reduced by 15 feet and the damage is reduced by 11 (2d10).

If the boulder’s speed is reduced to 0, it stops moving and is no longer a threat, though it may still block the entrance to the area behind it.

GM’s Note: Some trap makers use a hollow steel ball instead of a stone boulder. This is fitted with sharpened spikes that retract once enough weight is on them (more than 1,000 pounds). These spikes deal a further 22 (4d10) slashing damage to anyone in the boulder’s path. This damage is not reduced by a successful Dexterity check (this increases the trap’s CR to 12).

Raining Fire & Acid CR 14

Simple Mechanical Trap

Appearance An unlit hallway that is 40-feet long by 10-feet wide with a 25-foot high ceiling. Its floor tiles are made from alternating quartzite and granite tiles, forming a checkerboard pattern, and its walls consist of roughly-worked stone blocks with significant natural texture.

Trigger Twenty feet into the hallway, both 5×5 foot tiles in that line of the floor pattern act as pressure plates that will activate when 20 pounds of pressure is applied to them.

Detection A creature studying the ceiling will notice a cloth (camouflaged to appear as the stone ceiling) stretched across the ceiling with a successful DC 15 Wisdom (Perception) check.

A creature studying the flooring at 20 feet into the hallway will notice the two pressure plates with a successful DC 15 Wisdom (Perception) check.

Disarming or Destroying A successful DC 17 Dexterity check using thieves’ tools will disarm the trap as the hero uses wedges to keep the pressure plates from depressing.

Damage and Effects When the pressure plates activate, they release spring-loaded knives in the ceiling that cut the strings which secure the camouflaged cloth stretched across the ceiling. As the lines holding the camouflaged cloth are cut, the hidden glass bottles of alchemical reactants that were sitting on the cloth plummet to the floor. When the glass shatters and the chemical compounds mix, fire and acid bombs explode across the entire hall. Creatures in the area of effect must make a DC 17 Dexterity check.

On a failed save, a creature takes 14 (4d6) fire damage, 14 (4d6) acid damage, and 14 (4d6) piercing damage, or half as much on a successful save.

Snake Room CR 8

Complex Mechanical Trap

Appearance An empty room, 10-foot-by-10-foot, with two doors and no ornamentation. Dozens of slightly indented holes can be seen along the top of each of the four walls.

Trigger A minimum of two creatures enter the room, triggering the pressure plate underneath the room.

The doors lock when triggered by the pressure plate, after which the room floods with 4 poisonous snake swarmsMM. These swarms fill up every available space in the room, allowing them to attack any creature in the room.

This trap must be reset manually, such as by a druid using speak with animals.

Initiative The doors lock on initiative 20.

The snake holes open on initiative 15, and the swarms attack on initiative 15.

Detection A successful DC 15 Wisdom (Perception) check reveals the trap.

Active Elements Lock Doors: The door(s) to this room slam shut and are locked in place. This effect activates only once, the first time the trap is triggered.

Snake Holes: The snake holes open, allowing the swarms to flood in. This effect activates only once, the first time the trap is triggered.

Swarms: The poisonous snake swarm spends the first round filling up the room (and doing no damage).

Dynamic Elements The swarms attack each round after the first one, acting on initiative 15.

Constant Elements There are no constant elements to this trap.

Disarming or Destroying A successful DC 14 Dexterity check using thieves’ tools disables the trap by breaking the pressure plate. The doors are locked but can be opened with a DC 15 Dexterity check using thieves’ tools. The doors have an of AC 15 and 18 hit points and can be forced open with a DC 16 Strength (Athletics) check. Alternatively, the snakes can be calmed with a successful DC 18 Wisdom (Handle Animal). Anyone casting speak with animals gains advantage on this check.

Common Pit Trap

Mechanical Trap

Four basic pit traps are presented here.

Poison Darts

Mechanical Trap

When a creature steps on a hidden pressure plate, poison-tipped darts shoot from spring-loaded or pressurized tubes cleverly embedded in the surrounding walls. An area might include multiple pressure plates, each one rigged to its own set of darts.

The tiny holes in the walls are obscured by dust and cobwebs, or cleverly hidden amid bas-reliefs, murals, or frescoes that adorn the walls. The DC to spot them is 15. With a successful DC 15 Intelligence (Investigation) check, a character can deduce the presence of the pressure plate from variations in the mortar and stone used to create it, compared to the surrounding floor. Wedging an iron spike or other object under the pressure plate prevents the trap from activating. Stuffing the holes with cloth or wax prevents the darts contained within from launching.

The trap activates when more than 20 pounds of weight is placed on the pressure plate, releasing four darts. Each dart makes a ranged attack with a +8 bonus against a random target within 10 feet of the pressure plate (vision is irrelevant to this attack roll). (If there are no targets in the area, the darts don’t hit anything.) A target that is hit takes 2 (1d4) piercing damage and must succeed on a DC 15 Constitution saving throw, taking 11 (2d10) poison damage on a failed save, or half as much damage on a successful one.

Poison Needle

Mechanical Trap

A poisoned needle is hidden within a treasure chest’s lock, or in something else that a creature might open. Opening the chest without the proper key causes the needle to spring out, delivering a dose of poison.

When the trap is triggered, the needle extends 3 inches straight out from the lock. A creature within range takes 1 piercing damage and 11 (2d10) poison damage, and must succeed on a DC 15 Constitution saving throw or be poisoned for 1 hour.

A successful DC 20 Intelligence (Investigation) check allows a character to deduce the trap’s presence from alterations made to the lock to accommodate the needle. A successful DC 15 Dexterity check using thieves’ tools disarms the trap, removing the needle from the lock. Unsuccessfully attempting to pick the lock triggers the trap.

Poison Needle Trap

Source DiFP

Simple Mechanical Trap

A poisoned needle is hidden in the locking mechanisms of the chest. A successful DC 20 Wisdom (Perception) check allows a character to detect the presence of the trap, and a successful DC 15 Dexterity check using thieves’ tools disarms it. Attempting to pick the lock without first disarming the trap triggers the trap, whether the picking attempt is successful or not.

When the trap is triggered, the needle springs out, extending several inches out of the lock. A creature picking the lock takes 1 piercing damage and 11 (2d10) poison damage, and then must succeed at a DC 15 Constitution saving throw or be poisoned for 1 hour.

Collapsing Roof Trap

Mechanical Trap

This trap uses a trip wire to collapse the supports keeping an unstable section of a ceiling in place.

The trip wire is 3 inches off the ground and stretches between two support beams. The DC to spot the trip wire is 10. A successful DC 15 Dexterity check using thieves’ tools disables the trip wire harmlessly. A character without thieves’ tools can attempt this check with disadvantage using any edged weapon or edged tool. On a failed check, the trap triggers.

Anyone who inspects the beams can easily determine that they are merely wedged in place. As an action, a character can knock over a beam, causing the trap to trigger.

The ceiling above the trip wire is in bad repair, and anyone who can see it can tell that it’s in danger of collapse.

When the trap is triggered, the unstable ceiling collapses. Any creature in the area beneath the unstable section must succeed on a DC 15 Dexterity saving throw, taking 22 (4d10) bludgeoning damage on a failed save, or half as much damage on a successful one. Once the trap is triggered, the floor of the area is filled with rubble and becomes difficult terrain.

Crossbow Trap

Source TM

Mechanical Trap

When a creature steps on a pressure plate with more than 20 lbs. of force, or trips another type of proximity trigger, 1d6 crossbows make a ranged attack at +8 to hit at random creatures within a 10 foot by foot area around the trigger. A target that is hit takes 4 (1d8) piercing damage per hit.

The crossbows are hidden in the walls and usually concealed by wooden paneling. The DC to spot them is 16. Locating the trigger requires a DC 18 Intelligence (Investigation) check. The trap can be disabled by wedging the pressure plate or blocking the bolt holes.

Rolling Sphere

Mechanical Trap

When 20 or more pounds of pressure are placed on this trap’s pressure plate, a hidden trapdoor in the ceiling opens, releasing a 10-foot-diameter rolling sphere of solid stone.

With a successful DC 15 Wisdom (Perception) check, a character can spot the trapdoor and pressure plate. A search of the floor accompanied by a successful DC 15 Intelligence (Investigation) check reveals variations in the mortar and stone that betray the pressure plate’s presence. The same check made while inspecting the ceiling notes variations in the stonework that reveal the trapdoor. Wedging an iron spike or other object under the pressure plate prevents the trap from activating.

Activation of the sphere requires all creatures present to roll initiative. The sphere rolls initiative with a +8 bonus. On its turn, it moves 60 feet in a straight line. The sphere can move through creatures’ spaces, and creatures can move through its space, treating it as difficult terrain. Whenever the sphere enters a creature’s space or a creature enters its space while it’s rolling, that creature must succeed on a DC 15 Dexterity saving throw or take 55 (10d10) bludgeoning damage and be knocked prone.

The sphere stops when it hits a wall or similar barrier. It can’t go around corners, but smart dungeon builders incorporate gentle, curving turns into nearby passages that allow the sphere to keep moving.

As an action, a creature within 5 feet of the sphere can attempt to slow it down with a DC 20 Strength check. On a successful check, the sphere’s speed is reduced by 15 feet. If the sphere’s speed drops to 0, it stops moving and is no longer a threat.

Scything Blade

Source TM

Mechanical Trap

Typically released by a trip wire, the scything blade can also be swung by a suit of armor. When the trigger is released, the scythe makes a melee weapon attack against a creature within 5 feet at +6 to hit. On a successful hit, it does 6 (1d8 + 2) slashing damage.

The trip wire can be noted with a DC 14 Wisdom (Perception) check and the trap can be disarmed by carefully cutting the wire. This requires a DC 12 Dexterity check and failing the check by five or more triggers the trap.

Swinging Block

Source TM

Mechanical Trap

When, after placing more than 20 lbs of force on a pressure plate, a creature removes its weight from the plate, a large stone block swings across on metal chains. Any creature within 5 feet of the trigger must make a DC 15 Dexterity saving throw. On a failed saving throw, the creature takes 21 (6d6) bludgeoning damage. A creature that is moving normally feels the plate shift with a DC 18 Wisdom (Perception) check. If a creature is dashing when it steps on the plate, it has disadvantage on the check.

Disarming the trap once the trigger is detected requires a DC 18 Dexterity check with thieves’ tools.

Pit with Bees

Source RGG:DST

Mechanical Trap

Swarming Pit Traps: The stone stoop in front of my door contains a pit perfectly positioned so that anyone fiddling with my lock falls into it. You might scoff at the basic pit trap for being too commonplace for a sorcerer of my caliber, and you’d be correct. I supplement the common pit trap with hives of aggressive bees to bedevil the trespassers, stinging them to death while distracting them so much they can’t climb out. You can build hives into the walls of your pit to ensure a vigorous swarming, or you can prepare an enchantment to magically summon tenacious bees of an extraplanar origin.

The stone stoop covers a pit that’s 10 feet square, 10 feet deep, and full of swarming bees. A successful DC 11 Wisdom (Perception) check discerns the absence of foot traffic over the stoop. A successful DC 11 Intelligence (Investigation) check is necessary to confirm that the stoop is actually the cover of a pit.

When anyone steps on the stoop, it swings open like a trapdoor, causing the intruder to spill into the pit below. A creature falling into the pit must succeed on a DC 10 Dexterity saving throw or be swarmed by bees, taking 2 (1d3) piercing damage immediately. Creatures entering the pit thereafter must also succeed at this saving throw or become swarmed. A creature swarmed by bees must make another saving throw at the start of each subsequent round. Failure means the creature takes another 2 (1d3) piercing damage that round; success means the bees have stopped swarming the creature, who takes no further damage. A creature taking damage automatically ends the swarming by jumping into enough water to douse themselves, being subject to a moderate or stronger wind, or taking at least 3 points of damage from a damaging area effect. Rolling on the ground or smothering the creature with a cloak or similar permits the creature another Dexterity saving throw with advantage.

Once the pit trap is detected, an iron spike or similar object can be wedged between the stoop and the surrounding ground in such a way as to prevent the cover from opening, thereby making it safe to cross. The cover can also be magically held shut using the arcane lock spell or similar magic.

Pit with Yellowjackets

Source RGG:DST

Mechanical Trap

Swarming Pit Traps: The stone stoop covers a pit that’s 10 feet square, 20 feet deep, and full of swarming yellowjackets. A successful DC 15 Wisdom (Perception) check discerns the absence of foot traffic over the stoop. A successful DC 15 Intelligence (Investigation) check is necessary to confirm that the stoop is actually the cover of a pit.

When anyone steps on the stoop, it swings open like a trapdoor, causing the intruder to spill into the pit below. A creature falling into the pit must succeed on a DC 13 Dexterity saving throw or be swarmed by yellowjackets, taking 5 (2d4) piercing damage immediately. Creatures entering the pit thereafter must also succeed at this saving throw or become swarmed. A creature swarmed by yellowjackets must make another saving throw at the start of each subsequent round. Failure means the creature takes another 5 (2d4) piercing damage that round; success means the yellowjackets have stopped swarming the creature, who takes no further damage. A creature taking damage automatically ends the swarming by jumping into enough water to douse themselves, being subject to a moderate or stronger wind, or taking at least 6 points of damage from a damaging area effect. Rolling on the ground or smothering the creature with a cloak or similar permits the creature another Dexterity saving throw with advantage.

Once the pit trap is detected, an iron spike or similar object can be wedged between the stoop and the surrounding ground in such a way as to prevent the cover from opening, thereby making it safe to cross. The cover can also be magically held shut using the arcane lock spell or similar magic.

Pit with Murder Hornets

Source RGG:DST

Mechanical Trap

Swarming Pit Traps: The stone stoop covers a pit that’s 10 feet square, 20 feet deep, and full of swarming yellowjackets. A successful DC 15 Wisdom (Perception) check discerns the absence of foot traffic over the stoop. A successful DC 15 Intelligence (Investigation) check is necessary to confirm that the stoop is actually the cover of a pit.

When anyone steps on the stoop, it swings open like a trapdoor, causing the intruder to spill into the pit below. A creature falling into the pit must succeed on a DC 15 Dexterity saving throw or be swarmed by murder hornets, taking 10 (4d4) piercing damage immediately. Creatures entering the pit thereafter must also succeed at this saving throw or become swarmed. A creature swarmed by murder hornets must make another saving throw at the start of each subsequent round. Failure means the creature takes another 10 (4d4) piercing damage that round; success means the murder hornets have stopped swarming the creature, who takes no further damage. A creature taking damage automatically ends the swarming by jumping into enough water to douse themselves, being subject to a moderate or stronger wind, or taking at least 12 points of damage from a damaging area effect. Rolling on the ground or smothering the creature with a cloak or similar permits the creature another Dexterity saving throw with advantage.

Once the pit trap is detected, an iron spike or similar object can be wedged between the stoop and the surrounding ground in such a way as to prevent the cover from opening, thereby making it safe to cross. The cover can also be magically held shut using the arcane lock spell or similar magic.

Pit with Hellwasps

Source RGG:DST

Mechanical Trap

Swarming Pit Traps: The stone stoop covers a pit that’s 10 feet square, 20 feet deep, and full of swarming yellowjackets. A successful DC 15 Wisdom (Perception) check discerns the absence of foot traffic over the stoop. A successful DC 15 Intelligence (Investigation) check is necessary to confirm that the stoop is actually the cover of a pit.

When anyone steps on the stoop, it swings open like a trapdoor, causing the intruder to spill into the pit below. A creature falling into the pit must succeed on a DC 16 Dexterity saving throw or be swarmed by hellwasps, immediately taking 25 (10d4) piercing damage and 14 (4d6) poison damage. Creatures entering the pit thereafter must also succeed at this saving throw or become swarmed. A creature swarmed by hellwasps must make another saving throw at the start of each subsequent round. Failure means the creature takes another 25 (10d4) piercing damage and 14 (4d6) poison damage that round; success means the hellwasps have stopped swarming the creature, who takes no further damage. A creature taking damage automatically ends the swarming by jumping into enough water to douse themselves, being subject to a moderate or stronger wind, or taking at least 16 points of damage from a damaging area effect. Rolling on the ground or smothering the creature with a cloak or similar permits the creature another Dexterity saving throw with advantage.

Once the pit trap is detected, an iron spike or similar object can be wedged between the stoop and the surrounding ground in such a way as to prevent the cover from opening, thereby making it safe to cross. The cover can also be magically held shut using the arcane lock spell or similar magic.

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Magic Traps

Animated Fresco

Source TM

Magic Trap

A horrible fresco animates, causing all who can see it to make a DC 18 Wisdom saving throw. Those who fail drop whatever they are holding and become frightened for up to one minute. While frightened, a creature must take the dash action and move away from the fresco by the safest available route, unless there is nowhere to move. A creature who ends its turn in a location where it does not have line of sight to the fresco may make a DC 18 Wisdom saving throw, ending the effect on a success. After animating, the fresco cannot animate again for 24 hours.

Sphere of Annihilation

Magic Trap

Magical, impenetrable darkness fills the gaping mouth of a stone face carved into a wall. The mouth is 2 feet in diameter and roughly circular. No sound issues from it, no light can illuminate the inside of it, and any matter that enters it is instantly obliterated.

A successful DC 20 Intelligence (Arcana) check reveals that the mouth contains a sphere of annihilation that can’t be controlled or moved. It is otherwise identical to a normal sphere of annihilation.

Some versions of the trap include an enchantment placed on the stone face, such that specified creatures feel an overwhelming urge to approach it and crawl inside its mouth. This effect is otherwise like the sympathy aspect of the antipathy/sympathy spell. A successful dispel magic (DC 18) removes this enchantment.

Straw Needles

Source RGG:DST

Magic Trap

Several tiny, magical runes lie beneath the shaggy, durable material resembling straw that covers the tower’s exterior. The DC to spot a rune is 16. A spell or other effect that can sense the presence of magic, such as detect magic, reveals the rune and its aura of evocation magic. A successful DC 11 Intelligence (Arcana) check when examining a rune intuits that it creates magical backlash when the tower is attacked.

When a creature within 60 feet attacks the tower exterior, the rune magically launches three straw needles at the attacker. Each needle makes a ranged attack with a +4 bonus; vision is irrelevant to this attack roll. On a hit, the target takes 2 (1d4) piercing damage and must make a DC 11 Constitution saving throw, taking 4 (1d8) force damage on a failed save, or half as much damage on a successful save. The trap immediately resets, and thus launches a trio of needles after each attack on the tower exterior.

A successful dispel magic (DC 13) cast on a rune destroys it, but if the rune isn’t successfully dispelled, it launches its needles as though the dispel magic were an attack.

Straw Darts

Source RGG:DST

Magic Trap

Several tiny, magical runes lie beneath the shaggy, durable material resembling straw that covers the tower’s exterior. The DC to spot a rune is 16. A spell or other effect that can sense the presence of magic, such as detect magic, reveals the rune and its aura of evocation magic. A successful DC 13 Intelligence (Arcana) check when examining a rune intuits that it creates magical backlash when the tower is attacked.

When a creature within 60 feet attacks the tower exterior, the rune magically launches three straw darts at the attacker. Each dart makes a ranged attack with a +7 bonus; vision is irrelevant to this attack roll. On a hit, the target takes 2 (1d4) piercing damage and must make a DC 14 Constitution saving throw, taking 5 (1d10) force damage on a failed save, or half as much damage on a successful save. The trap immediately resets, and thus launches a trio of darts after each attack on the tower exterior.

A successful dispel magic (DC 14) cast on a rune destroys it, but if the rune isn’t successfully dispelled, it launches its darts as though the dispel magic were an attack.

Straw Arrows

Source RGG:DST

Magic Trap

Several tiny, magical runes lie beneath the shaggy, durable material resembling straw that covers the tower’s exterior. The DC to spot a rune is 18. A spell or other effect that can sense the presence of magic, such as detect magic, reveals the rune and its aura of evocation magic. A successful DC 13 Intelligence (Arcana) check when examining a rune intuits that it creates magical backlash when the tower is attacked.

When a creature within 60 feet attacks the tower exterior, the rune magically launches three straw arrows at the attacker. Each arrow makes a ranged attack with a +7 bonus; vision is irrelevant to this attack roll. On a hit, the target takes 3 (1d6) piercing damage and must make a DC 15 Constitution saving throw, taking 16 (3d10) force damage on a failed save, or half as much damage on a successful save. The trap immediately resets, and thus launches a trio of arrows after each attack on the tower exterior.

A successful dispel magic (DC 15) cast on a rune destroys it, but if the rune isn’t successfully dispelled, it launches its arrows as though the dispel magic were an attack.

Straw Spears

Source RGG:DST

Magic Trap

Several tiny, magical runes lie beneath the shaggy, durable material resembling straw that covers the tower’s exterior. The DC to spot a rune is 20. A spell or other effect that can sense the presence of magic, such as detect magic, reveals the rune and its aura of evocation magic. A successful DC 13 Intelligence (Arcana) check when examining a rune intuits that it creates magical backlash when the tower is attacked.

When a creature within 60 feet attacks the tower exterior, the rune magically launches three straw spears at the attacker. Each spear makes a ranged attack with a +8 bonus; vision is irrelevant to this attack roll. On a hit, the target takes 4 (1d8) piercing damage and must make a DC 15 Constitution saving throw, taking 27 (5d10) force damage on a failed save, or half as much damage on a successful save. The trap immediately resets, and thus launches a trio of spears after each attack on the tower exterior.

A successful dispel magic (DC 16) cast on a rune destroys it, but if the rune isn’t successfully dispelled, it launches its spears as though the dispel magic were an attack.

Fire-Breathing Statue

Magic Trap

This trap is activated when an intruder steps on a hidden pressure plate, releasing a magical gout of flame from a nearby statue. The statue can be of anything, including a dragon or a wizard casting a spell.

The DC is 15 to spot the pressure plate, as well as faint scorch marks on the floor and walls. A spell or other effect that can sense the presence of magic, such as detect magic, reveals an aura of evocation magic around the statue.

The trap activates when more than 20 pounds of weight is placed on the pressure plate, causing the statue to release a 30-foot cone of fire. Each creature in the fire must make a DC 13 Dexterity saving throw, taking 22 (4d10) fire damage on a failed save, or half as much damage on a successful one.

Wedging an iron spike or other object under the pressure plate prevents the trap from activating. A successful dispel magic (DC 13) cast on the statue destroys the trap.

Fire Breathing Suit of Armor

Source TM

Magic Trap

When a creature comes within fifteen feet of the armor, the armor releases a 15-foot cone of fire. Each creature within the cone must make a DC 16 Dexterity saving throw. Those that fail take 17 (4d6) damage while those that succeed take half as much.

The trap recharges on a 5 or 6 on 1d6. A variant of this trap is a fireplace breathing sparks instead.

Drowning Tentacles CR 6

Complex Magic Trap

Appearance A magical sigil on the bucket is activated by being disturbed, summoning tentacles that attack any creatures adjacent to the well. They attempt to drag the hero down and drown them.

Trigger The hemp fibers of the rope are woven in a pattern that forms a magical sigil. When the windlass is operated to lower the bucket, the sigil is activated and the spell is completed.

Detection A successful DC 15 Wisdom (Perception) or Intelligence (Arcana) check reveals the magical sigil. Detect magic reveals an aura of conjuration magic on the rope.

Initiative The tentacles act on initiative 20.

Active Elements Three rubbery tentacles reach up from the water in the well and randomly attempt to grab a creature in a square adjacent to the well. A targeted creature must succeed on a DC 15 Dexterity saving throw or take 16 (4d6) bludgeoning damage and be restrained by the tentacle.

Dynamic Elements Once a tentacle has restrained a target, it will retract on the next round, dragging the target underwater. On all subsequent rounds, the target automatically takes 16 (4d6) bludgeoning damage until the tentacles disappear or the 227277 target frees itself from the tentacles (whichever comes first). A creature restrained by the tentacles can use its action to make a DC 15 Strength (Athletics) or Dexterity (Acrobatics) check (its choice). On a success, it frees itself.

Constant Elements While restrained by the tentacles, the grabbed creature is dragged into the well and starts to drown. While a creature can normally hold its breath for a number of minutes equal to 1 + Con bonus, due to the strangling nature and tossing and twisting from the tentacles, this is reduced to a number of rounds equal to 3 + Con bonus.

Disarming or Destroying Dispel magic (DC 15) destroys the sigil. A successful DC 16 Intelligence (Arcana) check also destroys the sigil as the hero snips the rope fibers, unraveling the sigil. Failing the check triggers the trap.

last for 1 minute, after which time they dissolve harmlessly into water. The tentacles can’t be dispelled with dispel magic and are immune to all forms of damage except cold. Taking 5 points of cold damage immobilizes a tentacle (which has AC 10 and 30 hit points) for 1 round which prevents it from squeezing a creature and grants the creature advantage on its Strength or Dexterity check made to free itself.

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Mechanical AND Magic Traps

Divide & Conquer CR 6

Simple Magic Mechanical Trap

Appearance A metal chest secured with an average lock requiring a DC 10 Dexterity check using thieves’ tools to open.

Trigger The chest holds four ornate chalices which rest atop a false bottom. A successful DC 5 Wisdom (Perception) or Intelligence (Investigation) check reveals the false bottom. The top panel (or lid) of the false bottom is made of a thin sheet of lead. A magical insignia is penned on the underside of it. Opening the false bottom changes the orientation of the insignia from horizontal to vertical. This change in orientation triggers a teleportation spell.

Detection Because the insignia is inscribed on the inside of an object, it is not readily visible, so it cannot be detected until triggered. A successful DC 15 Wisdom (Perception) or Intelligence (Investigation) check reveals the magical insignia only if these checks are made in conjunction with magic. Detect magic does not function in this case because of the thin sheet of lead. If a creature that is aware of the lead sheet makes a successful DC 15 Intelligence (Arcana) check, they determine that a magical trap or valuable magic item may be underneath.

Disarming or Destroying Dispel magic (DC 16) destroys the insignia.

Damage and Effects One random creature in contact with the lead panel when the trap is triggered is teleported into a stone sarcophagus located in a different location within 100 feet. The sarcophagus can accommodate a Large or smaller creature.

Any creature that doesn’t fit these parameters is immediately shunted out of the coffin and suffers 22 (4d10) force damage. The stone panels of the sarcophagus are 4 inches thick.

The sarcophagus has 50 HP, a 17 AC, and resistance to acid and piercing damage. It has immunity to cold, fire, necrotic, poison, psychic, radiant, and slashing damage. A successful DC 20 Strength (Athletics) check will slide the stone cover off. A creature inside the sarcophagus suffers a -2 penalty on the check due to the cramped space. After 4 hours, air runs out in the sarcophagus and a creature inside begins to suffocate.

Fire Jets CR 4

Simple Magic Mechanical Trap

Appearance Holes in the walls or nearby statues show a slight bit of charring from heavy flames at some point in the past.

Trigger A creature steps on a hidden pressure plate or activation tile, releasing gouts of flame from the nearby holes (often camouflaged as the mouth of statues).

Detection A successful DC 15 Wisdom (Perception) reveals the pressure plate or activation tile.

Detect magic reveals an aura of evocation magic from the statues (though this only applies to the magical version of trap).

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools cuts or disables the pressure plate for the mechanical trap. For the magical version of the trap a successful dispel magic (DC 13) cast on the statue or the activation tile destroys the trap.

Damage and Effects When activated by a weight of more than 20 pounds, the fire holes (mouth of the statues if such are present) release a 30-foot cone of fire.

Each creature in the fire must make a DC 13 Dexterity saving throw, taking 22 (4d10) fire damage on a failed save, or half as much on a successful one.

Screaming Book CR 6

Simple Magic Mechanical Trap

Appearance A tattered ledger or diary on the table. It has no title, but a pen and vial of ink rest on the table beside the book.

Trigger Exposing the magical inscription on the first page by opening the book.

Detection Detect magic reveals an aura of evocation magic around the book.

Disarming or Destroying Dispel magic (DC 13) destroys the magical inscription.

Damage and Effects A loud boom rips from the pages. All creatures within a 20-foot-radius must make a DC 15 Constitution saving throw. On a failed save, a creature takes 16 (4d6) thunder damage and is deafened for 1 hour. On a successful save, the creature takes half as much damage and is not deafened.

GM’s Note: This trap is often used to alert sentries posted nearby of the presence of intruders.

The Demon’s Gaze CR 7

Simple Magic Mechanical Trap

Appearance Two demonic statues line the walls with one on either side of the corridor. The statues do not face each other but are set 5 feet above one another, each staring into the wall on the other side. Solid blue beams emanate from the eyes of one, while solid red beams emanate from the other.

Trigger A creature passes through one of the beams.

Detection A successful DC 14 Wisdom (Perception) check reveals that where the blue beams hit the wall there is a smattering of ice. Where the red beams hit the wall, there is scorching from fire.

Disarming or Destroying The trap cannot be disarmed through physical means, but can (temporarily) be disarmed through the use of dispel magic (DC 15). This subdues the trap for an hour.

A DC 17 Intelligence (Arcana) check reveals that the beams can be safely passed through if a creature touches both beams at once.

Damage and Effects Any creature passing through a beam must make a DC 14 Reflex saving throw. A target takes 8d6 damage on a failed save, or half as much damage on a successful one. The damage taken depends on the beam crossed: crossing the blue beam deals cold damage, crossing the red beam deals fire damage.

If a creature passes through both beams at once, no damage is taken.

Diseased Darts CR 9

Simple Magic Mechanical Trap

Appearance A ceramic tile mosaic covers the north wall of a 20-foot-square room.

Trigger A living creature approaching within 5 feet of the mosaic.

Detection A DC 15 Wisdom (Perception) check reveals that the mosaic is tied to a trap, but not how.

A successful DC 17 Intelligence (Arcana) check reveals that certain religious sects use rituals to imbue likenesses of their deities with magical power. Detect magic reveals an aura of divination and evocation magic on the mural.

A successful DC 17 Intelligence (Religion) check will reveal that the mosaic is in the form of a deity of disease and pestilence. Detect magic reveals an aura of evocation magic on the centered on the mosaic.

Disarming or Destroying A successful DC 15 Intelligence (Arcana) check reveals that a hallow spell counteracts the ritual magic used to create these mosaics.

Dispel magic (DC 16) destroys the mosaic.

Damage and Effects A creature with a good facet in their alignment that approaches within 5 feet of the mosaic will be targeted by a barrage of magical darts of force and disease that automatically strike.

The target takes 49 (11d8) force damage and is afflicted with cackle fever.

Once the trap is triggered, it must be reconsecrated to function again.

Fiery Portrait CR 10

Simple Magic Mechanical Trap

Appearance A high-quality painted portrait whose eyes follow anyone watching the painting. An inner glow illuminates the eyes, occasionally flaring as if firelight was reflected in them.

Trigger A creature walks within 5 feet of the portrait and looks it in the eyes.

Detection A successful DC 15 Wisdom (Perception) check reveals the trap. Detect magic reveals an aura of evocation magic on the portrait.

Disarming or Destroying The trap cannot be disabled, but destroying it is easy. It has AC 5 and 8 hit points and is vulnerable to slashing and fire.

Damage and Effects Any creature within line of sight of the portrait must make a DC 15 Dexterity saving throw as they are enveloped in a pillar of fire. Each creature takes 24 (8d6) fire damage on a failed save, or half as much on a successful one.

Creatures that fail the saving throw also catch fire taking 3 (1d6) damage at the start of its turn until they or an ally take an action to douse the fire.

Once the trap has been triggered, the person in the portrait fades from view and the trap becomes inactive. The person reappears an hour later, after which the trap becomes active once more.

Impaling Stalactite CR 10

Simple Magic Mechanical Trap

Appearance A natural, underground cavern has stalactites on the ceiling 50 feet above and stalagmites with loose rubble on the floor creating difficult terrain.

Trigger Stepping on a magical engraving carved into the floor, which is concealed under sand and pebbles, triggers the trap.

Detection A successful DC 17 Wisdom (Perception) or Intelligence (Arcana) check reveals the magical engraving. Detect magic reveals an aura of transmutation magic on the floor.

Disarming or Destroying Dispel magic (DC 16) destroys the magical engraving. A successful DC 17 Intelligence (Arcana) check also destroys the magical engraving as the hero chisels away at the engraving, successfully siphoning away its power without triggering it.

Damage and Effects As soon as a creature steps on the magical engraving, gravity is reversed in that 5-foot square and the triggering creature falls upward for 50 feet until it hits the ceiling. The creature can make a DC 15 Dexterity saving throw to avoid being impaled upon the stalactite directly above. On a successful save, the creature slams into the ceiling and takes 24 (6d6) bludgeoning damage. On a failed save, the creature takes the bludgeoning damage and an additional 12 (3d6) piercing damage as it is also impaled by a stalactite. Whether the creature is impaled or not, it immediately falls back down as the effect abruptly ends. The creature can make a DC 20 Dexterity (Acrobatics) check to roll with the fall. It takes 24 (6d6) bludgeoning damage on a failed save, or half as much on a successful one.

Mass Electrocution CR 10

Simple Magic Mechanical Trap

Appearance An unlit hallway, 5-feet wide by 100-feet long, has an area of flooring that is an inch lower than the rest. The first 10 feet on either end of the hallway is not depressed, leaving the rest of the hallway 1-inch lower than the standard floor level. A crack on the right hand wall allows brackish water to slowly seep onto the floor.

Another crack on the left hand side of the hall allows the water to drain, keeping the hall from flooding, but leaving the depressed area with 1 inch of constant standing water.

Trigger A creature approaches within 10 feet of the glyph of warding spell that is inscribed on the tile floor 50 feet into the hallway.

Detection A successful DC 5 Wisdom (Perception) or Intelligence (Investigation) check reveals the cracks and the uneven floor. Anyone making a successful DC 15 Wisdom (Perception) or Intelligence (Investigation) realizes that the water is actually coming in from the cracks, rather than draining out.

The glyph is inscribed on the floor under water and needs to be spotted ten feet away which adds to the difficulty of detecting the trap. A successful DC 17 Wisdom (Perception) or Intelligence (Arcana) check reveals the magical glyph. Detect magic reveals an aura of abjuration magic in a 10-foot radius of where the glyph is inscribed.

Disarming or Destroying Dispel magic (DC 17) destroys the glyph. A successful DC 17 Intelligence (Arcana) ability check also destroys the glyph as the hero unravels part of the magic pattern of the glyph.

Damage and Effects The glyph of warding was crafted using the explosive runes with the lightning option.

All creatures standing in the water when the glyph is triggered must make a Constitution saving throw DC 17. A creature takes 45 (10d8) lightning damage on a failed saving throw, or half as much damage on a successful one.

Mirage Menaces CR 12

Simple Magic Mechanical Trap

Appearance A hall or room filled with hundreds of mirrors.

When a creature enters, the door slams shut, revealing a mirror on the inside of it too.

Duplicates of the triggering creature then emerge from the mirrors, attacking it.

Trigger A creature stands in or walks past the center of the room.

Detection A successful DC 15 Wisdom (Perception) check reveals that the door will slam shut when a creature stands in the middle of the room, but not the rest of the nature of the trap.

Discovering this before it activates requires a successful DC 16 Intelligence (Arcana) check.

Detect magic reveals an aura of illusion magic on each of the mirrors.

Disarming or Destroying The trap cannot be disarmed through physical means, but can (temporarily) be disarmed through the use of dispel magic (DC 17). This subdues the trap for 24 hours.

The mirrors can be destroyed, but at least 10 mirrors must be destroyed before the mirrors cease functioning. The mirrors have AC 8 and 10 hit points. Any broken mirrors reform in 24 hours.

Damage and Effects When triggered, 5 doppelgangersMM appear from the mirrors, taking the exact shape of the triggering creature. These creatures attempt to slay the triggering creature, but if killed they simply vanish into smoke, and the mirror that they emerged from turns dark, showing a reflection of the triggering creature lying dead in a coffin.

Once all five creatures are killed, the Hall of Mirrors becomes inactive for 24 hours.

Caught Red-Handed CR 12

Simple Magic Mechanical Trap

Appearance A dressing room containing a vanity with a mirror and a cushioned bench. Several containers of makeup, a bottle of perfume, and a jewelry box rest upon the vanity. Three mannequins stand in various poses. Each mannequin has a wig on its head, a neckerchief at its throat, a bracelet on its wrist, and one or more rings (each with a different gemstone) on each hand.

Trigger Exposing the magical glyph inscribed on the mannequin’s finger by removing the ruby ring covering it.

Detection Because the glyph is inscribed on the finger under the ruby ring, it is not visible for inspection without moving the ring. An arcanist’s magic aura spell has been cast on the glyph to mask its magic, making it appear to be nonmagical.

GM’s Note: If a creature wants to make a visual inspection of the jewelry without handling it, A successful DC 20 Intelligence check reveals that the jewelry on display is costume jewelry.

Disarming or Destroying If dispel magic (DC 16) is cast on the trapped mannequin, it will automatically dispel the arcanist’s magic aura spell first, leaving the glyph active. A second dispel magic (DC 16) is required to dispel the glyph.

If a creature uses detect magic again, they notice that there is still an aura of abjuration magic emanating from the finger.

Damage and Effects As the ruby ring is taken off the mannequin’s finger a disintegrate spell targets the creature triggering the trap. The targeted creature must make a DC 16 Dexterity saving throw. On a failed save, the target takes 75 (10d6 + 40) force damage. The target is disintegrated if this damage leaves it with 0 hit points.

Curiosity Killed The Cat CR 15

Simple Magic Mechanical Trap

Appearance A closed, sturdy, iron door.

Trigger A creature’s reflection in the mirror (mounted on the wall behind the false door) triggers the magical trap.

Detection A successful DC 20 Intelligence (Investigation) check reveals that a thin piece of paper pushed under the door is stopped by an obstacle which indicates something unusual, but not the exact nature of the trap. Detect magic can’t reveal the magical inscription on the back of the mirror because it is located behind the 1-inch thick iron door. If a creature employs magic that allows them to see through objects in conjunction with a successful DC 20 Wisdom (Perception) check, they discover a magical inscription on the back of the mirror. They will also see that there is only stone, but no room behind the false door.

Disarming or Destroying Destroying the mirror is a simple matter of smashing it, but it must be done without showing your reflection. The mirror has an AC of 5 and 8 hit points. Dispel magic (DC 18) destroys the trap.

Damage and Effects A feeblemind (DC 18) spell targets the first creature reflected in the mirror.

Wheel of Death CR 16

Complex Magic Mechanical Trap

Appearance A 20-foot circular room with a single 3-foot high pillar in the middle, on which is placed a darkgray stone.

Trigger 2 rounds after a creature steps into the room.

Detection A successful DC 18 Wisdom (Perception) check reveals that the room itself is trapped, and reveals grooves and scrapes along the walls.

Detect magic reveals an aura of transmutation magic on the stone.

Initiative The doors lock on initiative 20.

Each of the walls of blades acts on an initiative of 15.

The gravity stone in the middle of the room acts on an initiative of 5.

Active Elements Lock Doors: The door(s) to this room slam shut and are locked in place, requiring a DC 20 Dexterity check using thieves’ tools to open.

This effect activates only once, the first time the trap is triggered.

Damage and Effects Two rounds after a creature enters the room the door(s) slam shut and 4 longswords emerge from each of the walls. The walls then start spinning at great speeds, while the dark stone in the middle starts emitting pulses that push living creatures out towards the walls.

This continues for 5 rounds, or until every creature in the room is dead, or the trap is disabled or destroyed, depending on what comes first.

GM’s note: Cleaning the room or disabling the trap for an owner is a simple matter of putting a cloth infused with lead over the stone in the room.

Wall Blades: The walls of blades start spinning up to speed. The longswords attack anyone within 5 feet of them. Each set of swords has a +10 bonus to the attack roll and deals 18 (4d8) slashing damage.

Gravity Stone: Each creature in the room must make a DC 18 Strength saving throw. On a successful save, the creature takes no damage and is moved 5 feet towards the walls. On a failed save, the creature is flung all the way out, ending up adjacent to the nearest wall.

Dynamic Elements Each round, for the next 4 rounds, the blades spin faster, increasing the damage by 1d8, to a max of 4d8.

Constant Elements Any creature that ends its turn within 5 feet of any of the walls are attacked as per the active Wall Blades.

Disarming or Destroying A successful DC 20 Dexterity check using thieves’ tools disables it. The trap can be destroyed by dealing 30 points of damage to it. It has an AC of 17. Each successful check disables one of the “wall blades”. Each of the 4 wall blades must be disabled or destroyed individually.

Alternatively, by succeeding on a DC 15 Intelligence (Arcana) check, the hero realizes that the trap can be disabled by putting a leadlined cloth over the gravity stone.

Dead Heads CR 4

Simple Magic Mechanical Trap

Appearance A corridor, 80-feet long by 5-feet wide by 15-feet high. There is a lit torch at the start and end of the corridor.

Trigger A pressure plate 50 feet down the corridor opens the hidden trapdoor in the ceiling and activates the magical rune inscribed underneath it.

Detection A successful DC 15 Wisdom (Perception) or Intelligence (Investigation) check will reveal the pressure plate on the floor or the trapdoor in the ceiling. Detect magic reveals a faint aura of necromantic magic around the edges of the pressure plate. Detect magic reveals an aura of necromancy magic emanating from the ceiling.

Disarming or Destroying A successful DC 15 Dexterity check using thieves’ tools will disarm the trap as the hero wedges the pressure plate in place. Dispel magic (DC 12) destroys the magical rune, but has no effect on the trapdoor.

Damage and Effects Necromantic magic imbues the twelve preserved heads hidden in the ceiling with a semblance of life for 1 round. As the trapdoor opens, the heads fall to the floor, attempting to bite the nearest creature on the way down.

If a creature is between 30 and 50 feet into the corridor, one falling head will attempt to bite it. Each head makes a melee attack with a +8 bonus. It deals 2 (1d4) piercing damage plus 9 (2d8) poison damage.

If the magical rune is dispelled but the trapdoor is still triggered, the twelve heads fall to the floor and all creatures 30 to 50 feet into the corridor must make a DC 10 Dexterity save or be struck by a falling head for 1 point of bludgeoning damage.

Greedy Fountain CR 4

Simple Magic Mechanical Trap

Appearance A functioning water fountain where gold coins can be seen at the bottom.

Trigger Any living creature that is adjacent to the fountain hears a magical suggestion in their mind.

Detection A successful DC 15 Wisdom (Perception), Intelligence (Investigation), or DC 15 Intelligence (Arcana) check reveals the presence of sigils painted onto the inside bowl of the fountain under the shallow water. Detect magic reveals auras of enchantment, illusion, and conjuration around the fountain.

Disarming or Destroying A DC 15 Intelligence (Arcana) check reveals that the trap can be destroyed by physically damaging the bowl of the fountain, which has an AC of 10 and 5 hit points, cracking and destroying the magical script. Dispel magic (DC 15) dispels the magical sigils.

Damage and Effects A creature adjacent to the fountain hears the following words (spoken in their native tongue) in their mind: “Place your weapons in the fountain.” If the creature can’t be charmed, it is immune to the effects. Otherwise, it must make a DC 16 Wisdom saving throw. On a failed save, the creature must immediately spend 1 round putting any handheld weapon(s) and up to two sheathed weapons it may have into the fountain. At the end of the round, any weapons the creature deposited in the fountain are teleported away to a locked chest within 100 feet.

The coins at the bottom of the fountain are illusory.

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Haunts

Haunts, by their nature, have the Magic trait, as well as the Haunt trait.

Animated Objects Haunt

Magic Haunt

Source TM

Magic Haunt

When one or more creatures enter the trapped region, up to 11 small or 5 medium weapons animate and attack them. On initiative 10, each weapon moves up to 30 feet towards a target and makes a melee weapon attack against a target within 5 feet at +6 to hit. Small weapons do 5 (1d6 + 2) slashing or piercing (as appropriate) damage on a hit while medium ones do 8 (1d10 + 3). Each weapon has AC 14 and is destroyed if it takes 18 hit points of damage. They are immune to necrotic, poison, and psychic damage. Casting dispel magic on a weapon causes it to revert to an inanimate state for one hour.

Commanding Visage

Magic Haunt

Source TM

Magic Trap

When a creature approaches within 10 feet of this large stone visage, it commands the creature to drink a potion of poison lying on the pedestal. The target of the command must make a successful DC 16 Wisdom saving throw or attempt to comply with it. A creature that succeeds on the saving throw is immune from further commands from this face.

There is a 50% probability that the stone face has 100 gp gems for eyes.

Hypnotic Brazier

Source TM

Magic Haunt

This brazier may stand in something resembling an elaborate ritual chamber – with candles, diagrams, tapestries and idols. Its magical flames create a hypnotic pattern. Any creature that looks upon it must succeed on a DC 16 Wisdom saving throw or be hypnotized by the brazier. A hypnotized creature may attempt a new saving throw at the end of each its turns. Once it has succeeded on a saving throw, the creature is immune to the brazier’s hypnosis for 24 hours. A hypnotized creature makes every effort to get amidst the brazier’s flames as quickly as possible. Each round that a creature spends in the fire it takes 27 (6d8) fire damage. Dispel magic cast with a level 4 spell slot dampens the hypnotic pattern for 1 round, giving any creatures needing to make a saving throw advantage.

Disembodied Hands with Chilling Touch

Source TM

Magic Haunt

When a creature enters a room being guarded by this trap, a pair of spectral hands appear and target it. Up to six pairs of hands may appear, one per creature in the area. On initiative 20, the hands move up to 50 feet to follow their target as long as the target is within the room, and make a spell attack against their target if they are within 10 feet of the target.

The attack is made at +7 to hit. On a successful hit, the target takes 3 (1d6) cold damage and, on a failed DC 15 Constitution saving throw, loses 1 point of Strength until completing a long rest.

Disembodied Hands with Vampiric Touch

Source TM

Magic Haunt

When a creature enters a room being guarded by this trap, a pair of spectral hands appear and target it. Up to six pairs of hands may appear, one per creature in the area. On initiative 20, the hands move up to 50 feet to follow their target as long as the target is within the room, and make a spell attack against their target if they are within 10 feet of the target. The attack is made at +7 to hit. On a successful hit, the target takes 14 (4d6) necrotic damage and cannot regain hit points until the start of the next round.

Magic Mouth

Source TM

Magic Haunt

When a creature comes within 30 feet of the magic mouth, it cries loudly for help. Make three random monster checks. The magic mouth then becomes inactive for one hour. A variant of this trap also casts arcane lock on all exits, increasing the DC to break them down or unlock them by 10.

Malevolent Mirage

Source TM

Magic Haunt

A wondrous hypnotic illusion appears. Any creature seeing the illusion must make a DC 16 Wisdom saving throw or use its movement and make the dash action to enter its area. Within the area covered by the illusion may be spiked pits, fire, or any other form of dangerous area. The illusion can be seen through with a successful DC 18 Intelligence (Investigation) check.

The mirage could originate from an idol, fresco, statue, gemstone (1d3 x 100 gp), etc.

Moving Executioner Statue

Source TM

Magic Haunt

If a creature comes within 5 feet of the statue without depressing the bypass switch to disarm it, the statue makes a melee attack at +10 to hit against it. On a hit, the target takes 15 (2d6 + 8) slashing damage. The statue continues to make attacks as long as a target is within range and the statue has not been destroyed or disarmed. The bypass switch can be located with a successful DC 18 Wisdom (Perception) check. The statue is destroyed if it takes 25 points of damage. It has an AC of 15. The statue may guard a pedestal with small gemstones of little value, or stand in a room resembling a shrine or temple.

Rapid Rot

Source TM

Magic Haunt

A creature who touches the object protected by this trap must make a successful DC 14 Charisma saving throw or it and all objects it is wearing or carrying instantly age 1000 years. For most creatures, this means instant death, leaving only grey, moldy dust remaining. Detecting the trap requires a successful DC 18 Intelligence (Arcana) check. Once the trap has triggered, it cannot do so again for 24 hours.

Note: This trap is always linked to an item of great worth (1d6 x 500 gp), usually prominently displayed and surrounded by grim reminders of death and decay. E.g. a solid gold bowl in a room full of graven stone skulls, dust and moldy cobwebs, held by the statue of Death personified.

Room Full of Diseased Corpses

Magic Haunt

Source TM

The corpses all have slimy doom. The disease can be recognized with a successful DC 15 Wisdom (Medicine) check. The corpses may be just piled up, or placed elaborately in wooden thrones, hung on hooks, sitting in plush chairs or any other arrangement. They are usually moldy and putrid, but some (25% probability) possess 1d3 pieces of jewelry, value 2d8 x 10 gp. Finding any treasure requires a DC 14 Wisdom (perception) check (and probably touching the corpses).