Colossus (Piotr Nikolaievitch Rasputin) joined the second generation of X-Men when he was invited from his farm to join Xavier and save the original X-Men. His first appearance in a comic book was Giant Sized X-Men #1 (1975). He is a mutant who has the ability to transform his body into organic steel granting him superhuman strength, stamina, and durability. He is also one of the tallest X-Men, standing at 7´5´´ high. He has joined such groups as the X-Men, Defenders and Excalibur. He was in two X-Men films, and played a large part in both.
He has been known to have had a relationship with fellow X-Men Kitty Pryde, also known as Shadowcat . This relationship was cancelled because of Marvel editors' disapproval of the age difference between the two. Colossus has starred as a powerful character in many games and his special attacks are usual small area burst attacks, i.e., ground stomps, shockwaves, even making his steel skin explode in the classic 6 player X-men arcade game.
He had died after sacrificing himself in order to save mutantkind from the legacy virus. He was recently returned to comics after being resurrected by an alien named Ord from Breakworld during Joss Whedon's run on Astonishing X-men.