X-Men: The Last Stand (2006)

When a cure is found to treat mutations, lines are drawn amongst the X-Men, led by Professor Charles Xavier, and the Brotherhood, a band of powerful mutants organized under Xavier’s former ally, Magneto.

A government-supported laboratory finds a cure for the mutants and the DNA of a powerful boy is used for it. However, the mutants must give up their powers and become human, hence splitting them.

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