6) Essex Corp/Proteus
As with Days of Future Past’s post-credits scene, the end of Apocalypse sets up a villain for future films to deal with. Here, an employee of Essex Corp retrieves a vial of Wolverine’s blood from Alkali Lake. The scene is hinting towards Nathaniel Essex, AKA Mr Sinister. According to writer/producer Simon Kinberg, we could see him in either The Wolverine 3 or Gambit, or maybe both.
Another villain who could also be on the way is Proteus, a reality-warping maniac. His real identity is Kevin McTaggert, the son of Moira. He was alluded to here when Moira mentioned that she had a boy called Kevin with her ex-husband. If the films take another decade jump, Kevin could be of an appropriate age to become Proteus next time around.