Spending Hit Dice Options by Monster Type

The following options are divided among the different monster types, such as aberration, fiend, or undead. A monster must be of that creature type to choose one of the listed Hit Dice options.

Aberration

When an aberration uses a Hit Die, the result should include plenty of alien, creepy, or frightening descriptions. At its best, an aberration exists outside the natural order, and everything about it screams unnatural. They act in unexpected ways and pursue motivations difficult—if not impossible—for most creatures to comprehend.

Alien Mind

The structure of the creature’s mind enables it to shrug off most psychic attacks.

Benefit(s): When targeted by an attack that inflicts psychic damage, as a reaction, the aberration can spend one Hit Die to gain advantage on any saving throw allowed against the effect. If the aberration spends two Hit Dice as a reaction, it instead gains resistance to psychic damage until the end of its next turn. Finally, if the aberration spends four Hit Dice as a reaction, it gains immunity to psychic damage until the end of its turn.

Alter Reality

The creature bends the laws of this dimension to its own benefit.

Benefit(s): As an action, when the aberration spends one or more Hit Dice (to a maximum equal to its proficiency bonus), it can alter reality in several possible ways. Decide how many dice the creature expends and consult the table below for the effects. Unless stated differently, this benefit lasts until the end of the creature’s next turn.

Challenge	Bonus
1	Gain proficiency in one saving throw (can be used as a reaction)
2	Gain immunity to one of the following conditions: charmed, frightened, or poisoned
3	Gain magic resistance (advantage on saving throws against spells and other magical effects)
4	Automatically end one condition affecting the aberration
5	Gain resistance to bludgeoning, piercing, and slashing damage from nonmagical attacks
6	Gain immunity to bludgeoning, piercing, and slashing damage from nonmagical attacks

Dimensional Warping

Distances shift and warp around the creature.

Benefit(s): As a reaction, the aberration can temporarily increase or decrease the distance between itself and one creature it can see. When using this option, the aberration spends a number of Hit Dice up to an amount equal to its proficiency bonus. For each die expended, it can increase or decrease by 10 feet the distance between it and the target creature. This warping has no effect on other creatures or their distance from the aberration. This alteration lasts until the start of the aberration’s next turn. This alteration could put it outside the range of a weapon or spell attack, or this alteration could put the aberration in range to use one of its powers.

The aberration can use this change in distance to move farther than its movement speed. It still triggers opportunity attacks if it leaves a threatened area, and it still must deal with the effects of any interposing terrain (e.g., difficult terrain, hazards, etc.).

Eldritch Power

The creature calls upon dark, eldritch magic from other dimensions.

Benefit(s): The aberration can cast a warlock spell from an expanded spell list of the GM’s choice (i.e., the one most thematically appropriate to the monster). Doing so costs one Hit Die for each level of the spell cast. If the creature does not have a spell save DC, then its spell save DC equals 8 + its proficiency bonus + its Charisma modifier. If the creature does not have a spell attack bonus, then its bonus equals its proficiency bonus + its Charisma modifier.

Grasping Tentacles

The creature’s grasping tentacles gain in strength once they latch onto the enemy.

Prerequisite(s): The creature must possess a melee attack involving a tentacle, pincer, or similar attack capable of grappling.

Benefit(s): As a reaction when the aberration has another creature grappled with a tentacle or similar physical attack (a tendril or pincer would also qualify), it can expend a Hit Die and add one-half the amount rolled (round down) to the target creature’s escape DC.

Note: This option is similar to the Crushing Grip feature described below (see the Brute monster role for details). It is more effective for larger aberrations, and it becomes especially dangerous for size Huge or Gargantuan aberrations (which roll a d12 or a d20, respectively).

Impossible Movement

The creature seemingly ignores gravity and the laws of reality to move across walls and ceilings.

Benefit(s): By spending a Hit Die, the creature gains a speed of 10 feet in a movement type it does not normally possess, such as a swim speed or climb speed. It cannot, however, gain a fly speed. For each additional Hit Die, the creature spends, its speed with this new movement type increases by 10 feet. This benefit lasts for 1 minute. A creature that gains a climb speed with this option also gains the spider climb ability, allowing it to climb difficult surfaces (including upside down on ceilings) without the need for an ability check.

Psychic Reflection

Peering into the mind of this creature carries a grave risk to those foolish enough to attempt it.

Benefit(s): If another creature uses a spell or magic item to reach into the mind of the aberration, such as with detect thoughts or any form of telepathy’ as a reaction, the aberration can spend a number of Hit Dice up to the value of its proficiency bonus. The creature casting such magic suffers 1d6 psychic damage for each Hit Die that the aberration spends.

Unnatural Vigor

The creature draws eldritch magic from alien dimensions to grow larger and tougher.

Benefit(s): As an action, the aberration can spend three Hit Dice. When it does so, it increases its size by one category (e.g., from Medium to Large, from Large to Huge, etc.). This effect lasts a number of rounds equal to the creature’s proficiency bonus. The increase in size changes its Hit Dice, and thus it’s hit points. When the effect ends, the creature returns to normal size, Hit Dice, and hit points. If this reduction in hit points, combined with any damage the aberration has already suffered, reduces it to 0 hit points, it dies immediately. The creature can only use this option once per combat.

Note: The GM should plan ahead whether a monster will use this feature in a battle and have the monster’s adjusted hit points already determined, as well as the difference between its standard hit points and its size-adjusted hit points.

Beast

Beasts usually possess animal-level intelligence and are therefore rarely the major monster in an encounter for mid or higher-level adventurers. If you want to give a beast a Hit Die option, the best route is to draw from those provided based on the monster’s role in the encounter, most likely from the Brute category described in this section.

As mentioned previously, for the most part, beasts usually are poor candidates for using Recovery Dice options. This category of creature includes mundane animals as well as giant varieties—creatures with limited intelligence that rarely feature prominently in important encounters. That being said, here are a few Recovery Dice options to consider giving to beasts for those times where the GM wishes to create an unusual or unique animal or to surprise players from time to time.

Celestial

When a celestial creature uses Hit Dice, it draws upon its innate otherworldly powers and extraplanar nature. The more powerful such beings, such as a planetar or a solar, tend to show off when they expend such energies with a bright show of light or similar effects.

Damage Resistance

Ordinary weapons may have trouble harming this creature.

Benefit(s): As a reaction or as a bonus action, the celestial can spend two Hit Dice to gain resistance to bludgeoning, piercing, and slashing damage from non-magical attacks. This protection lasts until the end of the celestial’s next turn. If the celestial spends three Hit Dice, it gains immunity to bludgeoning, piercing, and slashing damage from nonmagical attacks.

Enhanced Awareness

The celestial extends its perceptions magically.

Benefit(s): As a bonus action, the celestial can expend one or more Hit Die to increase its perceptive abilities as described in the table below. This enhancement lasts for one minute.

Hit Dice Spent	Benefit
1	Increase passive Perception by +5
2	Increase passive Perception by +10
3	Increase passive Perception by +10, increase darkvision range by 50%
4	Increase passive Perception by +10, increase darkvision range by 50%, gain truesight 60 feet

Fiery Flight

The celestial bursts aflame in mid-air, leaving a trail of fire in its wake.

Prerequisite(s): The celestial must possess a fly speed to use this option.

Benefit(s): As a bonus action, the celestial can spend one or more Hit Dice to ignite a trail of flame in its wake as it flies. As it flies, each creature it passes within 10 feet of must succeed at a Dexterity saving throw (DC = 8 + the celestial’s proficiency bonus + its Charisma bonus modifier) or take fire damage equal to 1d8 for each Hit Die expended. The celestial can expend a number of such Hit Dice up to its proficiency bonus. The flames dissipate when the celestial’s turn ends. A creature can only take this fire damage once per turn.

Inner Light

The celestial emanates a brilliant, blinding light in all directions.

Benefit(s): As an action, the celestial can spend two Hit Dice to emit a burst of bright light in a 60-foot-radius sphere. All non-celestial creatures in the area of effect must make a Constitution saving throw (DC = 8 + the celestial’s proficiency bonus + the higher of its Wisdom or Charisma modifier) or become blinded until the end of the celestial’s next turn. Otherwise, this light is considered bright light. If any of this effect’s area overlaps with an area of darkness created by a spell of 3rd level or lower, the spell that created the darkness is dispelled.

Magic Resistance

The creature’s extraplanar origins grant it a measure of protection against earthly magic.

Benefit(s): The celestial can, as a reaction or a bonus action, spend two Hit Dice to gain advantage on saving throws against spells and other magical effects until the end of its next turn.

Unearthly Charisma

The unearthly beauty of the celestial mesmerizes those creatures witnessing it.

Benefit(s): As an action, the celestial can spend three Hit Dice to emanate an aura of divine beauty, grace, and glory. All non-celestial creatures within a 60-foot-radius sphere that can see the celestial must make a Charisma saving throw (DC = 8 + the celestial’s proficiency bonus + its Charisma modifier) or become charmed. Creatures immune to charm automatically succeed at this saving throw. A charmed creature has disadvantage on Wisdom (Perception) checks made to perceive any creature other than the celestial. This effect ends for a creature if it can no longer see the celestial or if the celestial moves out of range or becomes incapacitated. The charm effect otherwise lasts until the end of the celestial’s next turn. It can, however, extend this duration by another turn by expending two more Hit Dice.

If any creature attacks a charmed subject, this effect automatically ends for that subject.

Construct

Since most constructs lack sentience, most of them do not have or use Hit Dice. If you design a major encounter with a construct as the boss monster or gravest threat, here are several options to consider.

Defensive Bastion

The construct roots itself in place and becomes immovable.

Benefit(s): As a bonus action, the construct can expend a Hit Die to root itself in place. From that moment until the end of its next turn, it becomes restrained but also becomes immune to any effect or attack that would force it to move, such as thunderwave or telekinesis.

Enhanced Perception

The construct perceives other creatures at greater distances, regardless of lighting conditions.

Benefit(s): The construct can spend one Hit Die as a bonus action to gain blindsight to a range of 10 feet. For each additional Hit Die the construct spends, increase its blindsight range by another 10 feet. If the construct already possesses blindsight, increase the range of its perception by 10 feet. This benefit lasts for 1 minute.

Juggernaut

Once the construct moves, nothing slows its progress.

Benefit(s): As part of its movement, the construct can spend a Hit Die to enable it to move through difficult terrain without penalty.

In addition, if the construct is restrained, as a bonus action, it can spend a Hit Die to attempt another saving throw, with advantage, to end that restraint. Alternatively, the construct can spend a reaction, and a Hit Die to attempt this saving throw (such as to avoid giving advantage to attacks made against it).

If the construct is grappled by an effect or another creature, it can spend a Hit Die and a bonus action (rather than an action) to make an escape attempt, gaining advantage on the roll when it does.

Regeneration

The construct repairs damage to its components.

Benefit(s): At the end of its turn, the construct can spend one Hit Die and regain that number of hit points. It must have at least 1 hit point left to use this option.

Dragon

With their massive size, tremendous strength, and devastating breath weapon attacks, a dragon should prove itself a worthwhile and devastating opponent, but with the focused attacks of 4 to 6 high-level adventurers, even a dragon can be challenged.

Adding a few additional options can make up for the disadvantage they face as a solo encounter and provide a more creative challenge for the party.

Dangerous Ground

The dragon’s breath weapon leaves the terrain broken and hazardous.

Prerequisite(s): The creature must have a breath weapon to use this option.

Benefit(s): The dragon can expend three Hit Dice as part of using its breath weapon. When it does so, the breath weapon affects creatures in its area as normal. In addition, the terrain within the area of effect becomes difficult terrain for 1 minute.

Finally, whenever a creature starts its turn standing on the affected terrain, they take damage equal to the dragon’s proficiency bonus. The damage type is the same as that inflicted by the breath weapon.

Deafening Roar

When the dragon unleashes its breath weapon, the thunderous sound overwhelms the hearing of those caught in its wake.

Prerequisite(s): The creature must have a breath weapon to use this option.

Benefit(s): When using its breath weapon, the dragon can spend two Hit Dice. Each creature inside the breath weapon’s area of attack that fails its saving throw also becomes deafened for 1 minute. A deafened creature can attempt a Constitution saving throw (the DC equals that of the breath weapon) at the end of each of its turns, ending the condition with a success. If a creature’s saving throw is successful or the effect ends for it, that creature is immune to the Deafening Roar for the next 24 hours.

Elemental Aura

The dragon exudes waves of elemental energy.

Prerequisite(s): The creature must have a breath weapon to use this option.

Benefit(s): As a bonus action, the dragon can expend two Hit Dice to exude an aura that causes the same type of damage as its breath weapon (e.g., a fire aura for a red dragon). While active, the aura deals 5 damage to any creature that ends its turn within 30 feet of the dragon. The aura continues until the start of the dragon’s next turn.

If the dragon instead spends 4 Hit Dice, the aura damage increases to 10.

Forceful Breath

The dragon’s breath weapon strikes with hammering force.

Prerequisite(s): The creature must have a breath weapon to use this option.

Benefit(s): The dragon can spend Hit Dice, up to the value of its proficiency bonus, to add bonus bludgeoning damage to its breath weapon. In addition to suffering the usual damage caused by the breath weapon, each creature in the area of effect also suffers 1d8 bludgeoning damage for each Hit Die expended. Even if the creature succeeded in its saving throw against the breath weapon’s primary damage, it still takes the full amount of bludgeoning damage. A creature that entirely avoids the breath weapon (such as a rogue using the Evasion class feature) avoids all bludgeoning damage. The bludgeoning damage is considered magical for purposes of damage resistance.

Grappling Bite

The dragon closes its enormous maw, clamping down on some unfortunate fool’s limb.

Prerequisite(s): The creature must have a bite attack and must be of size Huge or larger to use this option.

Benefit(s): When making a bite attack, the dragon can expend two Hit Dice to also make a grappling attempt as part of the bite. If the bite hits, the dragon grapples its target so long as the target is at least one size category smaller. The escape DC for this grapple equals 8 + the dragon’s Strength (Athletics) modifier. Each round the dragon maintains this grapple; it can automatically inflict bite damage on the grappled target, but it cannot use its bite attack against another target without releasing the grapple. In addition, the dragon cannot use its breath weapon while grappling a creature in this manner.

Hole in The Middle

The dragon demonstrates absolute control over its breath weapon, bringing destruction to its enemies but not its minions.

Prerequisite(s): The creature must have a breath weapon to use this option.

Benefit(s): When the dragon unleashes its breath weapon, it can spend one Hit Die for each creature in the area of effect it wishes to exclude. That creature does not need to make a saving throw against the breath weapon and suffers no harm for being in the area of effect.

Shake The Earth

The dragon slams its bulk into the ground, knocking nearby creatures to the ground with the impact.

Prerequisite(s): The creature must be size Huge or Gargantuan to use this option.

Benefit(s): As an action, a Huge-sized dragon can spend three Hit Dice to slam into the ground with all its weight. Each creature on the ground within 20 feet of the dragon must make a Strength saving throw (DC = 8 + the dragon’s proficiency bonus + its Strength modifier) or be knocked prone and take 1d8 bludgeoning damage.

For a Gargantuan-sized dragon, the area of effect increases to 30 feet, and the bludgeoning damage increases to 2d6.

Terrifying Presence

Mortals quiver in terror at the sight of such a magnificent creature.

Prerequisite(s): The creature must have the Frightful Presence ability in order to use this option.

Benefit(s): The dragon can amplify its Frightful Presence ability by spending a Hit Die as part of its action. When this happens, the dragon chooses a number of creatures it can see within 120 feet, up to the value of its proficiency bonus. Each creature targeted suffers disadvantage on their Wisdom saving throw to resist the dragon’s Frightful Presence ability.

Elemental

A few types of elementals work well with Hit Dice options, such as a djinni or an efreeti. Most elementals, on the other hand, aren’t intelligent or clever enough to make use of Hit Dice.

Elemental Growth

As the elemental stands within its element, it grows in size and power.

Prerequisite(s): the elemental must have immunity to damage from the element to which it holds affinity, such as fire damage, in order to use this feature.

Benefit(s): If the elemental enters a space that contains the element to which it holds an affinity (e.g., fire for an efreeti or water for a marid), as an action, it can spend three Hit Dice to enlarge its size by one category (e.g., Medium to Large, Large to Huge). This size increase lasts for a number of rounds equal to the elemental’s proficiency bonus, after which it returns to normal size.

The increase in size changes the elemental’s Hit Dice and hit points correspondingly. When the elemental returns to its normal Hit Dice and normal hit points, if any reductions due to combat reduce it to 0 hit points, it dies immediately.

Note: The GM should plan ahead whether a monster will use this feature in a battle and have the monster’s adjusted hit points already determined, as well as the difference between its standard hit points and its size-adjusted hit points.

Elemental Healing

The creature bathes in its elemental affinity, rejuvenating its life force.

Prerequisite(s): the elemental must have immunity to damage from the element to which it holds affinity, such as fire damage, in order to use this feature.

Benefit(s): If the elemental enters a space that contains the element to which it holds an affinity (e.g., fire for an efreeti or water for a marid), as an action, it can spend up to a number of Hit Dice equal to its proficiency bonus. For each Hit Die it spends, it heals 1d6 + its Constitution modifier in hit points.

Fey

Fey creatures delight in mischief. They manipulate the perception of other creatures, play tricks on the mind, and even tamper with luck. Whereas most creatures use Hit Dice to heal themselves or enhance their innate abilities and powers, fey are sometimes able to use these options to affect other creatures directly.

Cunning Disguise

The creature weaves a potent spell to hide its true nature.

Prerequisite(s): The fey must have the ability to cast disguise self or similar magic to use this option.

Benefit(s): When the fey casts disguise self or uses a magical ability that alters its appearance, it can spend a Hit Die. Thereafter for the next hour, any creature using an Intelligence (Investigation) check to discern the disguise suffers disadvantage on the roll.

If the fey spends two Hit Dice, it also treats its spell save DC as 2 higher, but only with regards to the disguise self spell’s effects.

Evasion

With a blur of motion, the fey avoids harm.

Benefit(s): If the fey is subjected to an effect that allows it to make a Dexterity saving throw to take only half damage, it can spend four Hit Dice to gain evasion against that effect. With evasion, the fey takes no damage if it succeeds on the Dexterity saving throw, and only half damage if it fails.

Fortune Favors The Bold

The fey warps reality, swapping its reaction time with that of another creature.

Benefit(s): The fey can spend three Hit Dice to swap its initiative score with that of another creature it can see within 120 feet. This swap remains in effect for the remainder of the encounter. The fey can make this swap at the start of the encounter when initiative is rolled, but it cannot use this option while surprised.

Overpowering Charm

When it chooses to do so, the fey’s charm becomes almost impossible to resist.

Prerequisite(s): The fey must have a power or ability that allows it to charm other creatures, whether by casting charm person or by other means.

Benefit(s): When the fey casts a spell or uses an ability that charms a target, it can spend three Hit Dice to affect a creature ordinarily immune to being charmed. The target creature still receives a saving throw to resist becoming charmed, but if it fails, the charm takes effect. The target creature remains charmed for up to 1 minute, although it can attempt another Wisdom saving throw at the end of each of its turns, ending the charm on itself with a success.

Thief of Time

The fey steals a moment of time from another creature and uses it for its own benefit.

Benefit(s): As a reaction, the fey can spend three Hit Dice and steal either a reaction or a bonus action from one creature it can see within 60 feet. If it steals a reaction, then it can use up to two reactions in the same turn. If it steals a bonus action, it can spend two bonus actions on its turn (all other limits concerning actions on a turn, such as with spellcasting, remain in effect). The target creature loses the stolen action for that turn (which might, for example, prevent it from making an opportunity attack). The fey must use the stolen action before the start of its next turn or lose that action.

Truesight

The fey sees past illusions and deceptions to see the truth of the matter.

Benefit(s): As a reaction, the fey can expend two Hit Dice to gain truesight with a range of 60 feet for 1 minute.

Fiend

A fiend, whether demon, devil or something else, stands as one of the best types of monster to have and use Hit Dice. These creatures tend to be cunning, intelligent, and use hit dice abilities. Given a fiend’s extraplanar origin, it may well possess unearthly powers drawn from hellish planes and nightmarish dimensions.

Acid Spittle

The creature spews a glob of acidic spittle onto its weapon.

Prerequisite(s): The fiend must have a melee weapon attack to use this option.

Benefit(s): As a bonus action, the fiend spends one Hit Die to exude a glob of acidic spittle onto a melee weapon it wields (a spear, sword, its own claws, etc.). The weapon does additional bonus acid damage equal to the fiend’s proficiency bonus on its next hit.

Aura of Impurity

Healing magic works poorly in the vicinity of the fiend.

Benefit(s): The fiend can activate this aura by spending an action and four Hit Dice. Any creature that starts or ends its turn within 40 feet of the fiend must make a Constitution saving throw (DC = 8 + the fiend’s Constitution modifier). on a successful save, the creature is immune to this aura for the next 24 hours. on a failed save, the creature only gains minimum benefit from any healing, magical or mundane, that it receives while within this area of effect, i.e., 1 point per die rolled. The aura lasts for 1 minute.

Corruption of Silver

Mere proximity to the fiend taints and tarnishes even the purest silver.

Benefit(s): The fiend can, by spending a bonus action and two Hit Dice, apply its damage resistance to nonmagical attacks from silvered weapons.

Demonic Rage

The fiend erupts into a bloodthirsty frenzy.

Benefit(s): As a bonus action, the fiend can spend three Hit Dice to enter a battle frenzy. While in this state, the fiend cannot cast spells or use any ability that requires concentration, and it cannot use ranged attacks. One of the fiend’s melee weapon attacks each round gains advantage and inflicts bonus damage equal to its proficiency bonus. The rage lasts a number of rounds equal to the fiend’s Constitution modifier (minimum of 1 round). The fiend can drop out of this frenzy as a bonus action.

Regenerating Magic

The creature draws upon its fiendish energies to replenish its spellcasting.

Prerequisite(s): The creature must possess the spellcasting ability in order to use this option. The fiend can regain an expended spell slot by spending a number of Hit Dice equal to the slot. Thus, to regain a 3rd-level spell slot, the fiend must spend three Hit Dice.

Sprout Wings

A pair of ragged, bat-like wings sprout from the monster’s back and it takes flight

Benefit(s): As a bonus action, the fiend can spend three Hit Dice to grow a pair of wings, gaining a fly speed of 30 feet. For each additional die spent, the fly speed increases by another 10 feet. The wings rot away at the start of its next turn.

Teleportation Capture

The fiend can teleport itself and a grappled creature.

Prerequisite(s): The fiend must have the ability to teleport itself to use this option.

Benefit(s): When the fiend uses an ability or power that allows it to teleport, it can expend three Hit Dice to allow it to teleport an adjacent creature. If the creature is unwilling, it can avoid being teleported by succeeding at a Dexterity saving throw (DC = 8 + the fiend’s Intelligence modifier). The fiend and the creature it teleports must observe all other restrictions for the teleportation, such as distance, line of sight requirement, etc.

Giant

A giant makes an excellent opponent for truly epic combat scenes. As such, a giant serves as a great candidate for using Hit Dice options. Most giants should use the options described under the Bodyguard or Brute monster.

Humanoid

For the most part, this type of monster is largely a catch-all. If you wish to give Hit Dice options to a humanoid, the best way is to base their choices on their role in a given encounter. Given that humanoids are such versatile creatures, they can fit any of the roles described.

Monstrosity

Although a number of intelligent, clever monsters exist within the monstrosity category, such monsters tend to favor brutal, savage attacks over finesse and subtlety.

The best options for them are found under the monster role of Brute presented previously in this chapter. In some cases, such as with an ankheg or centaur, the Skirmisher options may fit better.

If the monster often acts alone or utilizes special tactics that benefit a one-on-many scenario, the Solo options would be a great choice.

Ooze

A typical ooze lacks sentience or any sense of self and should not receive Hit Dice. Even an ooze or similar creature that possesses intelligence should rarely have or use Hit Dice unless it serves as the major monster in an encounter.

Plant

Most plants lack much in the way of intelligence or self-awareness and thus shouldn’t have Hit Dice. For those plants with some measure of sentience, such as a treant, here are a few possible options to choose from. Combine these creatively in addition to the normal plant abilities for some interesting effects.

Attack From Below

Gnarled roots and tendrils burrow up from the ground to attack the creature’s enemies.

Benefit(s): As an action, the plant can spend a Hit Die to make a melee weapon attack against a creature it can see within 10 feet. Treat this attack as one of the plant’s standard attacks, such as a slam attack for a treant or a constrict attack for a vine blight. For each additional Hit Die the plant spends, it can attack one additional target it can see within range. The plant can only attack each creature once with this feature.

Huge-sized plants can make this attack against a creature within a 20-foot-radius, while Gargantuan plants can make this attack against a creature within a 30-foot-radius.

Inhuman Mind

In spite of its intelligence, the plant’s mind is completely different from those of other creatures.

Benefit(s): As a reaction, the plant can spend a Hit Die to gain advantage on saving throws against attacks that inflict psychic damage until the end of its next turn. If the plant spends two Hit Dice it also gains resistance to psychic damage for that period of time; if it spends three Hit Dice, it gains immunity to psychic damage instead.

Tremorsense

The plant senses approaching creatures through vibrations in the ground.

Benefit(s): By spending Hit Die as a free action, the plant gains tremorsense to a range of 60 feet for 1 minute.

Undead

Weak and mindless undead should never have Hit Dice or options to use them. Even those undead with some mind of their own, such as a ghoul or a wight, should rarely have Hit Dice options. Hit Dice options are conscious decisions to use abilities in lieu of healing and so represent a certain appreciation for life and capability of thought.

These options should be reserved for dangerous, cunning undead such as liches, mummies, or vampires. When an undead creature uses Hit Dice, it draws upon whatever dark, malignant power animates and motivates them. They may not heal wounds, but they can use their necromantic energies to regenerate wounds or ignore conditions.

When an undead creature expends Hit Dice, use plenty of scary, ghoulish imagery to describe what happens the characters experience.

Ghoulish Recovery

The monster takes a bite out of a living creature, consuming blood and flesh to stitch closed its own wounds.

Prerequisite(s): The monster must have the ability to make a melee natural weapon attack, such as claws or a bite.

Benefit(s): The round after the undead hits a living creature with a natural melee weapon attack (e.g., a bite or claw), it can spend an action and one or more Hit Dice to regain hit points. The undead regains 1d6 hit points for each Hit Die spent. The creature may not regain more hit dice in this fashion than his target possesses.

Insubstantial

The monster can move through creatures and objects without difficulty.

Prerequisite(s): The monster must have the Incorporeal Movement ability to use this option.

Benefit(s): When the monster uses its Incorporeal Movement ability, it can expend one Hit Die to avoid taking force damage for ending its turn inside an object.

Incorporeal Quickness

The monster moves through creatures as if they weren’t there.

Prerequisite(s): The monster must have the Incorporeal Movement ability to use this option.

Benefit(s): When the monster uses its Incorporeal Movement ability, it can expend a Hit Die to move through other creatures and objects without treating them as difficult terrain until the start of its next turn.

Life Sense

The undead gains the ability to sense the nearby presence of the living.

Benefit(s): The undead can spend two Hit Dice as an action to sense the location of any living creature within 60 feet of it for 1 minute. This cannot detect constructs or undead creatures.

Recovery Drain

The undead’s touch drains even the reserves of its victim’s life force.

Prerequisite(s): The creature must have the Life Drain attack in order to use this option.

Benefit(s): When the creature hits a target with its Life Drain attack, it can spend one or more Hit Dice as a bonus action. For each die it expends, the target loses one of its own Hit Dice. Lost dice are restored to the creature at the end of its next long rest.

Touch of Decay

The touch of this undead horror causes flesh to rot.

Benefit(s): If an undead creature makes a melee weapon attack and spends three Hit Dice, the attack inflicts normal damage and, in addition, the target’s flesh begins to rot. Each round on its turn, the target suffers necrotic damage equal to the undead’s proficiency bonus. The affected creature can attempt a Constitution saving throw (DC = 8 + the undead’s proficiency bonus + the undead’s Constitution modifier) at the end of each of its turns, ending the effect on itself with a success. Once a creature succeeds at this saving throw, it becomes immune to this effect for the next 24 hours.

Undead Psyche

The mind of this undead creature is resistant to psychic damage.

Benefit(s): As a reaction, the undead can spend two Hit Dice to gain resistance to psychic damage until the start of its next turn. If the undead spends four Hit Dice in this manner, it gains resistance to psychic damage for 1 minute.