Nimrod

Nimrodis an advanced Sentinel from the future of New York in 2055 AD. He became a time traveller in order to stop Bishop.

Biography
When Bishop time-traveled to stop Senator Kelly's assassination, Nimrod followed him and faced the X-Men. Nimrod proves to be a formidable enemy and even when he's destroyed, he begins self-repairing before Bishop destroys the device allowing him to remain in the present day.

At a later point, Master Mold sent Nimrod and Fitzroy back in time to kill Charles Xavier before he created the X-Men, and told Nimrod afterwards to kill Fitzroy. They succeeded in killing Xavier at first, but this was undone again by Bishop, Shard and two mutants from the alternate timeline created by Xavier's death.