With phase three of the Marvel Cinematic Universe well underway and the groundwork currently being laid for phase four, there is constant speculation among Marvel fans as to exactly what one of the most powerful entities in the film world today will throw at us next. After all, they already seem to be branching out from their traditional, marketable heroes, into their more outlandish properties.

Plus, with their recent deal with Sony that allowed them to add Spider-Man to the mix, there's also been talk over if and when they'll be able to acquire some of the other hot properties that currently reside with other studios. So, naturally, a prospect that has come up among fans is that of an MCU version of the X-Men series, the rights to which currently belong to 20th Century Fox.

Some appear to like the idea of Marvel taking a crack at the X-Men and the studio even reportedly has contingency plans in place for if and when they manage to acquire the rights. That said, however, there are some inescapable problems with the idea. Problems that, frankly, suggest that the two franchises should stay completely separate, lest both of them suffer the consequences.

Just because two things are great, doesn't mean that they should necessarily be mixed.