10 Mutants Who QUIT The X-Men

10. Colossus

Piotr Rasputin is a Russian born mutant with the ability to transform his body into organic steel. He was recruited to the team by none other than Professor Xavier. He came calling on the Rasputin farm one day when he was looking for mutants to help save his original team from the sentient island, Krakoa.

Once they completed the mission, Piotr agreed to return to New York with the X-Men and become a regular member of the team. While living in Westchester, Piotr missed his family and farm back in Russian, but he also formed strong bonds with other X-Men like Storm and Wolverine.

However, Piotr wasn't the only mutant in his family, as both his brother and younger sister carried the x-gene.

One day, Piotr got word from Russian that someone had killed his parents and his baby sister Illyana was kidnapped by the Russian government. They hoped to use her powers for their means. Through a series of awful events, Illyana died, and Piotr became disenchanted with the X-Men.

He chose to join Magneto's group, the Acolytes. Piotr didn't fully embrace Magneto's views, though. He decided to stay with the group and try to impart some of Professor X's wisdom to temper their extremist views.