Once a hungry vagrant, Jack Cole lived beneath the sewers with a group of friends temporarily in the care of the Abomination. He heard voices in his head but couldn’t explain why – at least not until after the mutant known as X-Man paid them a visit. X-Man was looking for a girl named Threnody and challenged the Abomination for her hand. X-Man pretended to lose to the Abomination, then he and Threnody left together, but Jack Cole would never be the same again. For a brief moment, Cole's mind reached out to X-Man's, and something inside shattered into pieces. X-Man awakened the latent powers within Cole, but the process left him completely insane. Jack Cole was gone, and only Jackknife remained.
Jackknife lashed out at everyone around him, slaughtering those he once called friend. Cole eventually sought out X-Man, thinking him to be a cancer of the mind, and wanted to destroy all traces of him – including murdering all those who ever came into contact with him. Jackknife was relentless in his pursuit, and when he finally came into direct contact with his prey, all hell broke loose. Jackknife would not - could not be stopped, and he seemed immune to all of X-Man's abilities. Even when X-Man dropped an entire building down around Cole, Jackknife would not die. The battle was fierce and brutal, but in the end, Jackknife wasn’t able to complete his mission. X-Man ensnared Cole with exposed power cables and electrocuted him. Cole's physical body yet lived, but his brain had been fried. X-Man turned Jackknife's body over to medical technicians on the scene, but it appeared Cole would remain in a vegetative state indefinitely – leaving the world free from the menace of Jackknife.