Wolverine

It goes without saying why Hugh Jackman’s Wolverine cannot be replaced in the X-Men shared universe – at most, his role could be substituted with the one of X-23, even if that would make the X-Men timeline even more nonsensical.

However, the Marvel Cinematic Universe hasn’t introduced a superhero like Wolverine until now. Of course there are the fighters (such as Captain America) and the angry ones (go figure). But Logan is one of a kind, with his stamina, his healing factor, his tracking skills, and so on. Furthermore, with Disney, the character’s true potential from the comics could be explored – after all, Wolverine is regarded as one of the better hand-to-hand combatants of the Marvel comics.

So if you think that the fight between Cap and Bucky in Captain America: The Winter Soldier was an intense one, imagine having Steve facing a literally indestructible foe (yeah, he’d have to be one, at least until he regains his memories).