Wrythe

The Wrythe is a swampland on the southern bank, the Versex-side, of the Kingfisher River in Ustalav. Within the Wrythe, there is a notable rise in the land to a drier environment called the Boil, or derogatorily the Wart, on which has been established the small city of Carrion Hill.

Dark purple cockroaches, called carrion roaches, live in the Wrythe and have adapted well to the city in their midst eating through the vast quantities of waste from Carrion Hill. The locals capture the cockroaches and process them into a purple building material called middenstone.