They use secondary mutation to send a person's consciousness back in time. Because the physical strain of traveling back 50 years would destroy most minds, Wolverine (Logan) is the only one who can survive the journey due to his rapid healing. The Mission in the Past (1973)

When X-Men: Days of Future Past hit theaters in May 2014, it wasn’t just another superhero movie. It was an ambitious crossover event uniting the original X-Men trilogy cast (Hugh Jackman, Patrick Stewart, Ian McKellen) with the younger First Class ensemble (James McAvoy, Michael Fassbender, Jennifer Lawrence). Directed by Bryan Singer, the film bridged two timelines, rewrote franchise canon, and delivered stunning set pieces—most notably Quicksilver’s legendary kitchen scene.