Rat Swarm, Hivemind

Huge swarm of Tiny beasts, unaligned

Armor Class 10
Hit Points 136 (13d12 + 52)
Speed 30 ft.

10 (+0) 10 (+0) 19 (+4) 15 (+2) 12 (+1) 3 (-4)

Damage Resistances bludgeoning, piercing, slashing
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses darkvision 30 ft., passive Perception 14
Languages telepathy 30 ft.
Challenge 8 (3,900 XP)


  • Innate Spellcasting (Psionics). The swarm’s innate spellcasting ability is Intelligence (spell save DC 13). As long as it has more than half of its hit points remaining, the swarm can innately cast the following spells, requiring no components:
  • Keen Smell. The swarm has advantage on Wisdom (Perception) checks that rely on smell.
  • Swarming. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny beast. The swarm can’t regain hit points or gain temporary hit points. A swarm takes half damage from attacks that use an attack roll and double damage from effects that require it to make a saving roll. Creatures that are not swarms are impaired while they remain in the swarm’s space or within 5 feet of it and have disadvantage on attack rolls and Constitution saving throws to maintain concentration. The area of the swarm is considered difficult terrain.


  • Swarming Bite. Each creature that shares a space with the swarm automatically takes 17 (5d6) piercing damage or 10 (3d6) piercing damage if the swarm has half of its hit points or fewer.
Section 15: Copyright Notice

Legendary Planet Adventure Path (5E) © 2020, Legendary Games; Authors: Matt Goodall, Jim Groves, Steven T. Helt, Tim Hitchcock, Jason Nelson, Richard Pett, Tom Phillips, Mike Shel, Neil Spicer, Mike D. Welham

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