Most assume that otyughs originally evolved in swamps and moved into sewers as civilization encroached on their natural habitats. True or not, they are now one of the larger predators in those dank environs. Otyughs are territorial, but they have been known to form loose collectives, even giving each other important-sounding titles like "king of offal" and "duchess of slime" to indicate their rank and station in their sludgy underworld beneath the streets.