Trevor Fitzroy was the bastard son of Anthony Shaw, a wealthy man in the apocalyptic future of Earth-1191. As a youth, Fitzroy was not in control of his powers. He had a relationship of sorts with Ruby Summers, and managed to save her life, as well as those of the time-displaced Jamie Madrox and Layla Miller, when they were attacked by Sentinels but was killed in the process. Ruby begged Layla to save him using her power to bring people back from the dead but the terrible consequence of Layla's powers were that those she resurrected came back without souls.
Fitzroy joined the Academy for Xavier's Security Enforcers (XSE) and engaged in a relationship with Shard. He turned out to be a criminal though and was removed from the Academy. His wealthy father tried to protect his son for a while, but when Fitzroy was caught for murder, even he could no longer protect him. Fitzroy was captured and arrested by Bishop, Shard's brother and a XSE officer.
Fitzroy himself thought that he was merely a teleporter, but a secret group of XSE agents, known as the Xavier's Underground Enforcers (XUE) discovered that Fitzroy had the ability to travel through time. The XUE recruited Shard and freed Fitzroy. They hoped to change the past to create a better present, but Shard stopped them, when she was reminded how dangerous Fitzroy was. Fitzroy was returned to prison.
From prison, Fitzroy escaped to the present time with his minion Bantam. There, he became involved with a group known as the Upstarts, a competition set up by Selene to eliminate her rivals within the Hellfire Club. Lead by the Gamesmaster, the Upstarts had to kill other mutants to receive points. The Upstart with the most points would win the prize; control over the Hellfire Club and the other competitors. To enter the competition, one had to kill a member of the Hellfire Club's Inner Circle (though later members didn't have to.) As part of this “game,” Fitzroy unleashed Sentinels on the Reavers and their leader Donald Pierce, killing them all. Pierce escaped and arrived at the Hellfire Club, followed by the Sentinels. The Sentinels killed Pierce (though as a cyborg, he was rebuilt later) and then killed most of the the Hellions and put their leader, Emma Frost, into a coma. The X-Men, who had been negotiating with Frost, fought Fitzroy. Fitzroy was forced to open a large time portal, allowing prisoners from his own time to escape to the present. The prisoners attacked the X-Men, but stopped when three figures stepped through the portal: Bishop and fellow XSE agents Randall and Malcolm came to the present and went after Fitzroy, eventually killing the escaped criminals. Malcolm and Randall were killed though and Bishop would remain in the present and join the X-Men.
Fitzroy turned on Selene and captured her, but she managed to escape later. He also brought in Sienna Blaze to compete in the Upstart competition. Fitzroy clashed with the X-Men a second time when he tried to kill Forge, but managed to escape again. When the Gamesmaster declared that the new target for the Upstart competition would be former members of the New Mutants and Hellions, Fitzroy attacked X-Force, demanding they turned over Rictor and Warpath. X-Force leader Cable tricked Fitzroy into trying to absorb his life-energy, but as Cable's arm was inorganic, Fitzroy's powers used his own life-energy to open a portal, seemingly killing him.
Why the portal didn't drain his own life is still unknown. Fitzroy reappeared under the thrall of Selene as the White Rook of the Hellfire Club. He sometimes fights in an omnium mesh bio-armor, which is extremely powerful, nearly indestructible, and may possibly be activated on his mental command.
Fitzroy increased his power levels substantially and journeyed to a future timeline in which Earth was reduced to medieval technology levels. There Fitzroy set himself up as the Chronomancer and took over, using time-jumping robots with futuristic weapons to keep control. Then he had Shard brought to that time, where he kept her captive, but before his goons got her, they transported Bishop to Fitzroy's realm as well. Bishop, however, remained on the loose, and Fitzroy began to modify Shard to make her human again. His powers increased dramatically, to the point where he could freeze people in a type of stasis and open many more portals than before. In addition, his energy powered the Chronotroopers and his entire fortress. In the final battle, Fitzroy used Shard as bait for Bishop, and he captured his rival when Shard betrayed him. Fitzroy tortured Bishop mentally and physically before leaving him to "assume his destiny as Master of Time."
Fitzroy's plan was to become Time itself, a feat so ambitious that the Watcher came to observe. Unfortunately, Bishop had been freed by his companion Link, and arrived to stop Fitzroy from entering the giant portal he had created. A fight ensued, and Fitzroy emerged victorious and headed for the portal again. Bishop, drained of energy had no chance until Shard arrived and turned herself into energy again, forcing Bishop to absorb her and blast her at Fitzroy. Bishop missed, but Fitzroy hesitated enough that Bishop caught him and held him half in, half out of the portal until it closed on itself, cutting Fitzroy in half.
Fitzroy known as "the Mutant Traitor," under the orders of Master Mold, travels back in time to 1959 to murder Charles Xavier. In the cartoon, he does not kill those whose energy he absorbs, but knocks them unconscious for a few days.