Leech Demon

Family: Demons

Large fiend (demon), chaotic evil

Armor Class 17 (natural armor)
Hit Points 147 (14d10 + 70)
Speed 30 ft., swim 40 ft.

19 (+4) 16 (+3) 21 (+5) 11 (+0) 12 (+1) 7 (–2)

Damage Resistances cold, fire, lightning; bludgeoning, piercing, and slashing from nonmagical attacks
Damage Immunities acid, poison
Condition Immunities poisoned, prone
Senses darkvision 90 ft., passive Perception 11
Languages Abyssal, telepathy 120 ft.
Challenge 11 (7,200 XP)
Proficiency Bonus +4


  • Amphibious. The leech demon can breathe air and water.
  • Blood Sense. The leech demon can pinpoint, by scent, the location of creatures that aren’t Constructs or Undead within 30 feet of it.
  • Magic Resistance. The leech demon has advantage on saving throws against spells and other magical effects.


  • Multiattack. The leech demon makes one Bite attack and two Tentacle Bite attacks, or it makes two Bite attacks.
  • Bite. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 14 (3d6 + 4) piercing damage plus 9 (2d8) necrotic damage.
  • Tentacle Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) piercing damage and 4 (1d8) necrotic damage, and the leech demon can attach its tentacle to the target. The demon has two tentacles, each of which can attach to only one target. While a tentacle is attached, the demon can’t use that tentacle to make Tentacle Bite attacks, the target is restrained, and the demon doesn’t attack with the tentacle. Instead, at the start of each of the demon’s turns, each creature with a tentacle attached to it loses 11 (2d6 + 4) hp due to blood loss, and the demon gains temporary hp equal to that amount. The demon can add temporary hp gained from this attack together and can add it to temporary hp gained from Release Swarm. The demon’s temporary hp can’t exceed half its hp maximum. The leech demon can detach one or both tentacles as a bonus action. A creature, including the target, can use its action to detach the demon’s tentacle by succeeding on a DC 17 Strength check.
  • Release Swarm (Recharge 5–6). The leech demon shakes loose dozens of leeches, creating a leech swarm (see Tome of Beasts 2 or use a swarm of poisonous snakes). The swarm acts as an ally of the leech demon and obeys its spoken commands. The swarm remains for 1 minute, until the leech demon dies, or until the demon dismisses it as a bonus action. If the leech demon is within 5 feet of the swarm, it can use its action to consume the swarm, gaining temporary hp equal to the swarm’s current hp. It can add temporary hp gained in this way with temporary hp gained from its Tentacle Bite attack. The demon’s temporary hp can’t exceed half its hp maximum. The demon can have only one swarm active at one time.


Hundreds of leeches cling to and crawl around this serpentine creature, which has a toothy maw filling most of its face. It raises two tentacles, revealing similar toothy maws lining each tentacle.

Leech demons prefer to spend their time on the Material Plane, where their unsettling appearance draws more of a reaction and where they can better inflict suffering. They especially enjoy infesting their victims’ bodies with leeches, which burst forth from the corpses to wreck havoc on the victims’ loved ones.

Implements of Swampland Revenge. Rumors proliferate about rituals to summon leech demons to right a grievous wrong. The demons gleefully wreak vengeance on their targets and try to ensure their summoners witness the gruesome deaths. The stories fail to disclose the demons demand a price from their callers, usually paid by the life of someone dear to them. Only the most desperate benefit from calling leech demons for retribution, as they often have no problem offering themselves up as payment when the demons complete their deeds.

Section 15: Copyright Notice

Tome of Beasts 3 © 2022 Open Design LLC; Authors: Eytan Bernstein, Celeste Conowitch, Benjamin L. Eastman, Robert Fairbanks, Scott Gable, Basheer Ghouse, Richard Green, Jeremy Hochhalter, Jeff Lee, Christopher Lockey, Sarah Madsen, Ben Mcfarland, Jonathan Miley, Kelly Pawlik, Sebastian Rombach, Chelsea Steverson, Brian Suskind, Mike Welham

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