Avengers: Doomsday - Character Breakdown

You could argue that no member of the X-Men was portrayed as differently, or had their story changed as much after the soft reboot as Mystique. Rebecca Romijn's iteration of the character was something of Magneto's right-hand woman, whereas in First Class it was revealed that she was all but family to Charles Xavier.

Of course, she flirted with a life of villainy throughout Days of Future Past, but ultimately stayed by Charles' side until her death at the hands of Jean Grey (Sophie Turner) in Dark Phoenix. The inclusion of Mystique makes the X-Men here very intriguing indeed.

In theory, this all but confirms this will be an all-new X-Men team. Since Mystique died in the 1990s, while Charles Xavier still looked like James McAvoy rather than Patrick Stewart, there is no way she could return with the team as old as they will be in Doomsday.

Yes, characters have come back from the dead before, but Raven (Jennifer Lawrence) was impaled and unquestionably killed. It's far more reasonable to assume that this will in fact be a new version of the X-Men, which may go a long way to explaining the omission of the likes of Halle Berry's Storm, Famke Janssen's Jean Grey, and Hugh Jackman's Wolverine.