The Planerat's Guild

The Planerat's Guild is an organization created by and for Sigil's population of sentient rats, providing a support network for rats seeking to explore the planes and avoid the many catlike predators in Sigil and elsewhere. Their headquarters is deep beneath the city's sewers. They have connections with the Clock Rats in Automata. Meetings of the Planerat's Guild are biweekly, and it is there that rat burglars, cranium rats, and others conspire and trade the latest chant on rat-sized portals and gate keys.

Several times in the history of the Guild sub-sects have broken off, but these groups, generally too weak to survive on their own, generally rejoin the Guild within a few rat generations. Currently the Xaosirats have built their own headquarters and work to introduce anarchy into the Planerat's Guild's operations with some success.