Crast, also called food-kin, were a race of crustaceans from Pria. They had a symbiotic relationship with the Priapulins. Crast eggs began to be incubated after being digested by a Priapulin. The Crast were willing to act as Priapulin food, and in return Priapulins cared for their children.
- Rogue Planet (As food-kin)