Leng Spider

Huge fiend (mythic), chaotic evil

Armor Class 20 (natural armor)
Hit Points 384 (24d12 + 96)
Speed 40 ft.

16 (+3) 24 (+7) 18 (+4) 22 (+6) 20 (+5) 22 (+6)

Saving Throws Dex +13, Int +12, Wis +11, Cha +12
Skills Deception +18, Insight +11, Perception +11, Stealth +19
Damage Resistances necrotic, psychic
Damage Immunities poison
Condition Immunities charmed, frightened, poisoned
Senses darkvision 120 ft., passive Perception 21; detect magic
Languages Aklo; tongues
Challenge 17 (18,000 XP)

Special Traits

  • Innate Spellcasting. A leng spider�s innate spellcasting ability is Intelligence (spell save DC 20). It can innately cast the following spells, requiring no material components:
    • At will: dispel magic, fabricate (web constructs only), freedom of movement
    • 3/day each: wind walk, invisibility, major image
    • 1/day each: charm monster (as charm person except it effects any creature type), insanity (as confusion but the duration is 1 day) mirage arcane, seeming
  • Legendary Resistance (3/Day). If a Leng spider fails a saving throw, it can choose to succeed instead.
  • Magic Weapons. A Leng spider’s weapon attacks are magical.
  • Spider Climb. The Leng spider can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
  • Transdimensional Perception. A Leng spider can perceive the Ethereal Plane, the Plane of Shadow, and the Dimension of Dreams (unless Leng is also currently inside the Dream Dimension) from Leng and the Material Plane. By expending one use of its legendary actions it can phase its melee and bite attacks across the dimensional barriers to attack the inhabitants of those planes. By expending two uses of its legendary actions, a Leng spider can ensnare a target with its web strand and pull the target to the same plane unless it succeeds on a DC 20 Intelligence saving throw.
  • Web Sense. While in contact with a web, the Leng spider knows the exact location of any other creature in contact with the same web.
  • Web Walker. The Leng spider ignores movement restrictions caused by webbing.
  • Web Weaponry. A Leng spider is talented at using its webs to construct weapons and tools. This technique of weapon creation allows the spider to effectively create a flail or bolas by attaching a heavy object such as a rock or chunk of metal to a cord of webbing. The spider attaches one end of this webbing to a leg and can then wield the weighted cord like a flail or bolas (treat as a net). It can only wield one such weapon at a time � it must use its other legs to walk. If a Leng spider drops or loses a web weapon, it takes 1 minute to create a replacement weapon, provided it has access to heavyweight objects of the correct size (such as loose rocks or skulls).


  • Multiattack. The Leng spider makes three web-flail attacks.
  • Bite. Melee Weapon Attack: +13 to hit, reach 5 ft., one creature. Hit: 7 (1d8 + 3) piercing damage, and the target must make a DC 20 Constitution saving throw, taking 18 (4d8) poison damage on a failed save, or half as much damage on a successful one. If the poison damage reduces the target to 0 hit points, the target is stable but poisoned for 1 hour, even after regaining hit points, and is paralyzed while poisoned in this way.
  • Web-Flail. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 12 (1d8 + 8) bludgeoning damage plus 10 (3d6) poison damage, and if the target took any poison damage it has disadvantage on the next attack roll it makes before the Leng spider’s next turn. In addition, if the target is Medium or smaller, the Leng spider can make a Strength (Athletics) check as a bonus action to shove the target and knock it prone.
  • Web. Ranged Weapon Attack: +13 to hit, range 30/60 ft., one creature. Hit: The target is restrained by webbing. As an action, the restrained target can make a DC 20 Strength check, bursting the webbing on a success. The webbing can also be attacked and destroyed (AC 10; hp 15; vulnerability to fire damage; immunity to bludgeoning, poison, and psychic damage).

Legendary Actions

A Leng spider can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature�s turn. A Leng spider regains spent legendary actions at the start of his turn.

  • Attack. The Leng spider may use one of its available attack options (except Multiattack).
  • Cast a Spell (Costs 2 Actions). The Leng spider casts one of its innate spells.
  • Shifting Dreamscape (Costs 3 Actions). The Leng spider rapidly takes the form of several nightmarish creatures, lashing out at all nearby. Each creature within 10 feet of the Leng spider must succeed on a DC 20 Dexterity saving throw or take 18 (4d8) damage of a type chosen by the spider: acid, cold, fire, lightning, or necrotic.


Leng spiders are intelligent, carnivorous spiders with hideously bloated bodies, though they can move with terrifyingly fluid grace. An adult has a legspan of 20�30 feet or occasionally more, but smaller (younger) specimens are common. An adult weighs 1-3 tons. Since they never stop growing, a few are far larger. They vary in color from deep purple to lambent orange.

Trapster. Leng spiders are sly and design traps for their prey. These can be elaborate and often involve treasure as bait. They are clever enough to let some adventurers live after finding the treasure, to entice further visitors to their mountain lairs. They delight in preying on humanoid egos and spring traps when a would-be treasure-seeker is most confident. Leng spiders thrive on being underestimated.

Dream Stalkers. These murderous beasts are not terrestrial at all but hail the mysterious plateau of Leng beyond the Dimension of Dreams. Both in their home realms and in their nests and networks in the mortal world, Leng spiders have a complex society and are readily able to wage war on those who infringe on their territory. Unless in their homes, they rarely fight to the death and will retreat if severely wounded to plot their revenge.

Section 15: Copyright Notice

Mythos Monsters (5E) © 2020, Legendary Games; Authors Michael "solomani" Mifsud, Robert J. Grady, Mark Hart, Jeff Ibach, Alex Riggs, Scott D. Young, Jeff Lee, Matt Kimmel, and Jason Nelson.

This is not the complete section 15 entry - see the full license for this page