Kro was the leader of the Deviants. Kro came to Earth thousands of years ago, but was trapped in ice for millennia, while the rest of his kind were exterminated by the Eternals. Due to glacial melting as a side effect of the impeding Emergence of Tiamut the Communicator, he and an isolated legion of Deviants were freed. Kro killed Ajak, gaining her power, and began hunting down the Eternals in a quest for power, eventually gaining a sapience never before experienced by a Deviant. Kro followed the Eternals as they tried to stop the Emergence, but was ultimately killed by Thena after failing to absorb her power.