When his genetic mutation manifested, Kevin Ford accidentally killed his father with his lethal and uncontrollable touch. Subsequently recruited as a student at the Xavier Institute, Ford found companionship in a student training squad called the Hellions, instructed by co-headmaster Emma Frost. Ford was later arrested and charged with his father's death, but the incident was deemed accidental by a criminal court in Atlanta, Georgia. Nonetheless, Ford would likely have fled before his trial had an attempted breakout by several of his fellow students been successful. An outcast even among his mutant peers, Ford is to be considered an extreme security risk. He met and developed a crush on Laurie Collins. However, when he decayed the skin off the cyborg Donald Pierce, Dani Moonstar was forced to stop him by showing him his worst fear - killing Laurie. In the aftermath of this, and realising that using his power "felt right", he left the Institute.
Some months later, Dani, with the help of Emma Frost set out to bring him back to the school, to fill the sixth place on the formalised New Mutants squad, mentored by Dani. While Kevin was still angry at Dani, Emma managed to persuade him to return, and he joined the New Mutants squad under the codename Wither. Clashing with Elixir, the current object of Laurie's affections who he'd last seen as one of Pierce's Reavers, Mercury, the only person he could touch without killing, reached out to him, having developed a crush on him. Shortly after he returned to the school he was arrested by the FBI for killing his father. While the Hellions tried to "rescue" him (Mercury coming in through a window to let him know), the New Mutants tried to stop them - fearing the consequences of involving the Institute in a fight with the FBI - until the X-Men arrived and ended the fight, taking them all back to the Institute before they were discovered. This was the final straw, however, and he swapped squads with Icarus to become a Hellion.Recently, he discovered Elixir's former relationship with Wolfsbane and released it to the school, successfully ending Josh's relationship with Laurie. During House of M|M-Day, when most of the world's mutants lost their powers, Kevin mistakenly thought he had lost his powers also. He touched Laurie's hand making it withered and after feeling more guilty and depressed he ran away from the Institute.
Recently, Wither joined Selene's Inner Circle and died fighting Elixir.