Polyroach

Each polyroach is an inch-long, beetlelike roach with a light brown wing case over useless wings; it cannot fly. A colony may hold up to 200. Twenty can pile together and fuse into a large roach about 18 inches long, fifty make a huge one 4 feet long, and all 200 can become a giant 6 feet long. Merging takes a full round, while breaking apart is instantaneous.

At any size its eyesight is poor. It relies on its antennae, which sense movement out to 120 feet and detect anything it considers food within 60 feet. Like all true roaches it is extremely quick and can reverse speed or direction in an instant.

Single roaches never attack anything bigger than themselves and have no attack statistics. The merged forms have stronger mandibles and can bite hard, though they would rather scavenge than chase live meals that run or fight back. Any bite has a 10% chance of passing on a disease like those spread by rats, and simply living with an infestation gives each resident a 5% chance per week of catching it.

A large or bigger polyroach that is losing a fight scatters, instantly splitting back into tiny roaches that run off in every direction. Every hit point of damage it took kills one of the little roaches, so a carpet of dead bugs falls to the floor, and a hungry attacker may stop to eat those while the living ones escape.

They eat nearly anything, including garbage, whitewash and the bindings of books. Small forms infest homes, raiding kitchens and pantries for crumbs and often living inside the walls. They are nocturnal and lair in dark places such as cellars, crawlspaces and dumps. Light does not hurt them but sends them running. A single female can lay up to 400 eggs, so clearing out an infestation is usually a long war. Almost everyone finds them revolting.

As scavengers they sit at the bottom of the food chain and are no great threat, yet a 6-foot cockroach is enough to send many adventurers running. They have no known magical use, though wizards who specialize in polymorph magic might study how so many bodies merge so quickly and so well.