Cletus Kasady, a deranged and sociopathic serial killer, merged with an alien symbiote to become the notorious supervillain Carnage. After a dark and disturbed childhood that included burning down an orphanage, Cletus was convicted of multiple life sentences. While incarcerated at Ryker’s Island Prison, he became cellmates with Eddie Brock, who had been separated from the Venom symbiote. When the alien returned to rescue Eddie, it left behind its offspring, which bonded with Cletus, transforming him into the monstrous Carnage.