Rat Swarm
Medium natural beast (swarm)
Level 2 Skirmisher XP 125

Initiative +6        Senses Perception +6; low-light vision
Swarm Attack aura 1; the rat swarm makes a basic attack as a free action against each enemy that begins its turn in the aura.
HP 36; Bloodied 18
AC 15; Fortitude 12, Reflex 14, Will 11
Resist half damage from melee and ranged attacks; Vulnerable 5 damage from close and area attacks
Speed 4, climb 2

(⚔) Swarm of Teeth (standard, at-will)

+6 vs AC; 1d6+3 damage, and ongoing 3 damage (save ends).

Alignment Unaligned        Languages -
Str 12 (+2)      Dex 17 (+4)      Wis 10 (+1)
Con 12 (+2)      Int 2 (-3)      Cha 9 (0)

Description: The common rat is a shy rodent with sharp teeth and a long, whiplike tail. Monstrous varieties take on a more fearsome countenance.
    Hundreds of feral rats crawl over each other in a ravenous, screeching horde.

Published in Monster Manual, page(s) 219, FR1 Scepter Tower of Spellgard, page(s) 24, H1 Keep on the Shadowfell, page(s) 38.