Lesser Cranium Rat Swarm (5e Creature)
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Lesser Cranium Rat Swarm
Medium swarm of Tiny monstrosities, neutral evil
Proficiency Bonus +2
Swarm. The swarm can occupy another creature's space and vice versa, and the swarm can move through any opening large enough for a Tiny rat. The swarm can't regain hit points or gain temporary hit points.
Bite. Melee Weapon Attack: +2 to hit, reach 0 ft., one creature in the swarm's space. Hit:' 7 (2d6) piercing damage, or 3 (1d6) piercing damage if the swarm is at half points or fewer.
Mind Blast (Recharge 5-6). The swarm emits a barrage of harmful psychic energy within a 60-foot cone. All non-cranium rats in the area must succeed on a DC 10 Wisdom saving throw or take 10 (3d6) psychic damage and be stunned until the end of their next turn.
Merge. The swarm merges with another adjacent lesser cranium rat swarm, the two forming an average cranium rat swarm together.
Cranium rats appear as normal rats with exposed brains and a malicious gleam in the eye. Individually they pose no more of a threat than a common rat, but in large numbers they develop a hive-like awareness of pure malice and gain the ability to use limited magic. They are commonly found in settlements on the Lower Planes and their gate-towns, as well as the sewers of Sigil where it is rumored a powerful cranium rat hive mind comprised of hundreds lurks. Sages conjecture the cranium rats may be servants of Ilsensine or some other unfathomable power using them as spies.