When Sentinels began attacking innocent mutants in U.S. cities, young Bobby Drake, who had recently discovered his own ice-forming powers, ran away from home to protect his parents. The Sentinels caught up with him in Times Square, but so did the newly formed X-Men, who rescued him and took him in. Dubbed Iceman by his team mate the Beast, Bobby battled the Brotherhood of Mutants alongside the X-Men, rescuing the President's kidnapped daughter and bringing about the end of the government-sponsored Sentinel attacks. The X-Men later fought reprogrammed Sentinels in Washington, saving many innocent lives. After spending some time back with his parents, he returned to the X-Men only to be kidnapped by Weapon X; following several weeks in captivity, the X-Men were freed by the Brotherhood.

Iceman confronted his deepest fears while fighting telepathic mutant David Xavier (son of X-Men founder Charles Xavier) in Scotland. During a rematch with David in Berlin, Bobby's terror initially immobilized him. Urged on by Professor X, he overcame his fear when his team mate Storm was threatened; he was severely injured.. Bobby spent weeks in the hospital, and his parents withdrew him from the school. The family's medical bills were paid by anti-mutant Senator Andrew Border Turk, who then pushed the Drake family to sue Xavier for $50 million, hoping to put the school out of business. Since Bobby's father lost his job when people found out he had a mutant child, the Drakes agreed. At a live press conference, Bobby refused to read Turk's prepared statement, instead dropping the action, stating he knew the risks of the mission and had learned integrity from Xavier.

When the X-Men became fugitives after it was revealed Xavier had lied about killing Brotherhood leader Magneto, Iceman defied his parents and helped the X-Men escape the Ultimates. The X-Men subsequently captured Magneto and saved the world, publicly redeeming themselves.

Bobby began dating his team mate Rogue, but foolishly kissed Kitty Pryde at the Coney Island fair, hurting Rogue. She soon left the X-Men in the company of Gambit, much to Bobby's distress. Iceman accompanied Marvel Girl, Cyclops and Kitty to Genosha to investigate whether Longshot was truly a murderer, and during the trip he and Kitty became a couple. However, Kitty dumped him when she learned he was still in touch with Rogue by e-mail, and clearly still in love with her.