Swarm of Dretches

AC 12

HP 45 (6d10 + 12)

Speed 40 ft.

Resistances Bludgeoning; Cold; Fire; Lightning; Piercing; Slashing

Immunities Poison

Condition Immunities Charmed, Frightened, Grappled, Paralyzed, Petrified, Poisoned, Prone, Restrained, Stunned

Senses Darkvision 60 ft., Passive Perception 9

Languages Abyssal; telepathy 60 ft. (works only with creatures that understand Abyssal)

CR 4

Traits

Fetid Aura. con 12, any creature that starts its turn in a 10-foot Emanation originating from the swarm. Failure: The target has the Poisoned condition until the start of its next turn. While Poisoned, the target can take either an action or a Bonus Action on its turn, not both, and it can't take Reactions.

Swarm. The swarm can occupy another creature's space and vice versa, and the swarm can move through any opening large enough for a Small creature. The swarm can't regain Hit Points or gain Temporary Hit Points.

Actions

Multiattack. The swarm makes two Rend attacks.

Rend. Melee Attack Roll: +4, reach 5 ft. Hit: 12 (3d6 + 2) Slashing damage, or 9 (3d4 + 2) Slashing damage if the swarm is Bloodied.