10 Ways The X-Men Films Nearly Turned Out Very Differently

In X-Men: Days of Future Past, Mystique murders President Richard Nixon, which causes the downfall of civilisation. Decades later, the surviving mutants have Wolverine time-travel to 1972 to stop her. For this plan to succeed, Wolverine requires Magneto's help but can't reach him since he was imprisoned for the alleged murder of President John F. Kennedy. Wolverine tracks down Quicksilver and asks him to break Magneto out of his cell.

The original director, Matthew Vaughn, envisioned Juggernaut as the one who helped Mags escape, not Quicksilver. The unstoppable character would've been played by Josh Helman (who ended up playing Stryker in the finished film).

When Bryan Singer took the helm, he swapped Juggers out for Mags' son, Quicksilver. Singer thought the silver-hared mutant would work better since his relationship with his father would add more conflict. (Since this conflict is never addressed, many viewers suspect Quicksilver was inserted into the story so Marvel Studios couldn't use the character in Avengers: Age of Ultron.)

Vaughn also wanted the Kennedy assassination to play a much bigger part in the story, and would eventually reveal that Bolivar Trask had JFK murdered and then framed Magneto to discredit mutantkind.