History
Colossus joined Magneto as a member of his Brotherhood of Evil Mutants until the Juggernaut (Charles Xavier) defeated him and Colossus joined his X-Men. Colossus lived a comfortable life as a member of the X-Men but began getting second thoughts about life under the Juggernaut's rule. When Cyclops declared that he was leaving the X-Men, Colossus joined him, and together with other dissenters, they allied with Magneto in defeating the Juggernaut. Colossus was easily dispatched by the Juggernaut, but it was all part of a plan that allowed the rebels to defeat him.[1]