Piotr Rasputin - aka Colossus - is a heroic character from Marvel Comics and a long-time member of the X-Men. He has appeared in several of the X-Men films in which he has been portrayed by Daniel Cudmore.
Piotr Rasputin was born in Russia prior to the Chernobyl nuclear disaster. The event caused several mutants in the area to manifest their powers at an early age, including Piotr, who developed the ability to transform his skin into organic steel. In this form, Piotr was immune to most physical assaults and possessed superhuman strength. He would immigrate to the United States during his teens and enrolled at Charles Xavier's School for the Gifted, eventually joining the X-Men.
Despite his intimidating size and strength, Colossus is a kind and gentle soul. He has a fondness for art and is always willing to step in to defend those who cannot defend themselves.
X-Men: Days of Future Past
Colossus is one of the few surviving mutants in the dystopian future of 2023. He meets a violent end when a fleet of Sentinels discover the Free Mutants' hideout in China and attack. Though Colossus puts up a valiant struggle, he is overwhelmed by the murderous Sentinels. Two of the killer robots grab him by the arms and legs and pull, ripping him in half even while he is in his armoured form.
Because Wolverine succeeds in preventing Mystique's murder of Bolivar Trask in 1973, the Sentinel program is halted before it can advance and lead to the nightmarish future. As such, Colossus' death is undone and he is living happily among his fellow X-Men at the Xavier Mansion in the revised timeline.