Fortress Sewer Rat

Few places hold as much stray evil magic as the sewers beneath a ruined fortress-city near a northern inland sea, and these rats are its offspring. They look like oversized sewer rats with coarse, glossy black bristles, but they have glowing yellow eyes and eerily humanlike faces. They reek of mildew and sewage, and some scholars think they even have a crude language.

These rats attack only in groups of three or more; one or two stay hidden. Each pack follows a leader that has maximum hit points (8 per Hit Die), and if it dies the rest must check morale.

They bite with long, sharp incisors. On a natural 20, the rat locks onto its victim and drains blood for an extra 1d4+1 damage each round. Prying it loose takes a full round and a successful open doors roll, during which the victim can do nothing else beyond thrashing and screaming, though the DM may allow half movement.

Their magic works like a cloak of displacement: the first attack against any one of them always misses. Brilliant light pains them, giving -2 to attack in daylight or continual light.

Despite the name, they live in any damp underground space near the city with plenty of water and rot: swamps, marshes, flooded cellars, even graveyards on wet ground. They never go out in daylight, not even under heavy clouds. A lair, always dark, moist and out of the way, holds 6d6 adults plus half again as many young, the young having half an adult's Hit Dice and damage. Lairs often hold leftover belongings of past victims.

They are vicious even by rat standards, and some scholars joke that the temper of the fallen tyrant god seeped into them. They never mix with lesser rats or with most creatures that summon rats, and they consider jermlaine a delicacy. Only vampires, tanar'ri and baatezu can manage them, and poorly at that.

Wizards wary of hunting phase panthers have tried sewing cloaks of displacement from these rats' pelts, so far producing only cloaks of flattened, stitched-together rat hides. Rumor says certain alchemists seek a potion or salve that copies the rats' displacement, and such buyers, if they exist, pay 500 gp for a rat dead no more than 48 hours.