Cryoks, otherwise known as the "Space Yetis" come from a planet that was being invaded by the Ceruleans, evil transforming robots.
The chieftain of the Cryoks is Ator. They lived in an ice village. The village was protected by a defector of the Cerulean army but Coop destroyed him when he mistook M.E.G.A.S. for an enemy. Ator then explained this to Coop and Coop in return became their guardian, for a short time.
Coop helped them defeat the Ceruleans while at the same time destroying the planet Surell which kept their planet cool. All the ice melted and the Cryohocks now live on a warm planet with large tropical beaches thanks to Coop.