Medium Swarm of Tiny Undead, Neutral Evil
Armor Class 12 Initiative +2 (12) Hit Points 49 (11d8) Speed 30 ft., Climb 30 ft.
Saving Throws Str +2, Dex +2, Con +0, Int −3, Wis +0, Cha −3
Damage Resistances Bludgeoning, Piercing, Slashing
Damage Immunities Necrotic, Poison; Charmed, Exhaustion, Frightened, Grappled, Incapacitated, Paralyzed, Petrified, Poisoned, Prone, Restrained, Stunned
Senses Blindsight 30 ft.; Passive Perception 10
Languages Understands Common but can't speak
Challenge Rating 3
The swarm can occupy another creature's space and vice versa, and the swarm can move through any opening large enough for a Tiny creature. The swarm can't regain Hit Points or gain Temporary Hit Points.
Melee Attack Roll: +4, reach 5 ft. Hit: 20 (4d8 + 2) Necrotic damage, or 11 (2d8 + 2) Necrotic damage if the swarm is Bloodied. If the target is a Medium or smaller creature, it has the Prone condition.