A squirming, roiling mass of squeaking rats draws closer, teeth flashing and claws scratching everything in its path.
A rat swarm typically consists of a biting, roiling mass of hundreds of disease-ridden rats driven to uncharacteristic heights of aggression by fantastic and overwhelming hunger. In such numbers, they become voracious hunters, capable of killing a full-grown human with hundreds of bites. Rat swarms are often found in the sewers of large human settlements. Rat swarms surround and attack any warm-blooded prey in their path.