A krashak is a magical construct, that is nearly immortal and indestructible. It is described as having "four arms, twice man height, face like a boar and taloned hands...no sign of genitals, nipples or navel, and the color of clay."
They have been known to come out of the Pelagirs, but they can also be created as needed by mages who know how. As they are a creature of High Magick, they are vulnerable to Earth Magick. Defeating one requires getting in close enough to throw a mixture of salt, moly and Lady's Star into its mouth. The construct will fall apart. In Oathbreakers, Jadrek defeats one this way.