Proteus

Proteus is Kevin MacTaggert – the son of existing X-Men movie character Moira MacTaggert – and he is one of the few X-Men villains who could truly present more of a threat than Apocalypse after he arrives in the franchise.

When his mutant abilities started to manifest in the comic books, he became a being of pure energy and was able to possess the bodies of humans in order to make himself tangible. However, such was the level of his power, he quickly burnt out every body he inhabited and had to move between bodies with alarming regularity – effectively killing people as he did so – in order to remain tangible.

His main power is that of reality warping – and that makes him one of the deadliest, most powerful foes the X-Men have ever faced, because he can effectively make anything he wants to happen occur just by willing it. He is also a very powerful telepath.

Like Cassandra Nova, he would represent a very different type of threat to anything seen before in an X-Men movie, as even killing the bodies he inhabit does nothing but free his energy form. He is, therefore, extremely hard to defeat.