The X-Men are a huge part of the world of Marvel Comics and have been a major ongoing franchise for FOX. However, one huge problem also stuck around for the studio and became increasingly worse as the movies progressed.

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That problem is, of course, the continuity of the films and how many issues it created. Some fans don't necessarily realize how many issues there are with the continuity but here's 10 that some people may not have noticed about the mutant franchise.

X-MEN AGES

The X-Men First Class cast lined up and looking down

The ages of the X-Men have consistently changed throughout and have been a major source of concern for those who study the continuity of these films. As the prequel series has progressed, often there are huge time leaps between each of the films.

However, the actors have not aged accordingly to the time period it's set in. As a result, many of the main characters have almost not aged at all. When we see the older versions of their characters, therefore, the ages don't really line up, causing a lot of issues.

DIFFERENT XAVIERS

The continuity for Charles Xavier has been all over the place. Whether he can stand or not, or if he is even alive has been an ongoing problem throughout the series. For the prequel films, Xavier's journey into the wheelchair is well documented.

However, when Xavier appears at the end of Wolverine: Originshe is standing once more. He is killed later on in the series but then returns again back to life, without any kind of explanation. Are there multiple versions of the character we are unaware of?

SABRETOOTH'S RELATIONSHIP

During the same origin film, Sabretooth and Wolverine are revealed to be brothers. Although it was one of the worst films of the franchise it did set up an interesting relationship between the two. However, this seems to be completely forgotten about.

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We are aware that Logan had his mind wiped and therefore is unable to remember the fact that Sabretooth is actually related to him. However, when we see the characters meet again you'd think there would be some kind of mention of this from the brother that can remember.

WALKING CHARLES

We've already mentioned how Charles seems to be pretty inconsistent with whether he can walk or not, as well as his age, but the issues only get worse. During the final part of the original X-Men trilogy, a young Charles and Magneto are shown meeting Jean.

However, the two are de-aged significantly for this meeting, although not to the level of the prequels and indeed this throws up questions around who the other Jean is, therefore. But what's more, Charles is standing once again only adding to the ongoing confusion.

MYSTIQUE

Mystique has been one of the main characters in the prequel series and has actually joined the X-Men rather than the brotherhood of evil mutants. However, in the original trilogy, she was presented as a villain which confuses matters.

Not only this but Mystique is actually killed in the most recent addition to the franchise, which is set before the original X-Men films where the character is very much alive. It seems like thinking too deeply into this will create multiple more continuity errors.

MULTIPLE DEADPOOLS

We all know that Ryan Reynolds has previously played the character of Deadpool. The original version had his mouth stitched up and laser eyes, as well as metal swords coming from his wrists. There's a major continuity error here.

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These films are all supposed to be part of the same canon. Perhaps there was a way to write around there being two versions of the merc with a mouth, however, the end of Origins shows that Wade Wilson is actually still alive. Perhaps there are two versions of Deadpool out there too.

X-MEN CAMEO

Deadpool X Mansion

Speaking of Deadpool, the second film actually has a cameo from the X-Men from the prequel series. However, the film is set within the same time period as the original films, suggesting that actors like Patrick Stewart should be portrayed in the group.

It's clearly supposed to be confusing as this part of the franchise is known for mocking the rest of the films. However, thinking about this for a second, having those versions of the characters really makes no sense to the rest of the FOX movies.

ANGEL

Angel is presented as one of the horsemen of Apocalypse during his huge invasion. Yet, the character has already appeared on film before. The prequel version of the character is largely forgettable and there to fill a spot.

However, the Angel from the original series has a major role to play in the fight between mutants and humans. He's obsessed with becoming a human, even trying to cut off his wings before accepting who he truly is. It's a shame the continuity actually gets in the way of the story.

TOO MANY FROSTS

Emma Frost in X-Men First Class

There's a way to write around this error but it is still a glaring one. During the breakout of the mutants in Origins, a version of Emma Frost appears. She's blond, can turn into diamonds and appears to know the way out through her mental abilities.

However, before this time period, we're introduced to another version of Emma Frost. While the two characters could be related, it still seems like a very avoidable mistake that once again caused a continuity error which doesn't even help with the story.

ADAMANTIUM CLAWS

It's well documented that underneath the adamantium skeleton of Wolverine, there is a bone structure. Therefore, his claws used to be made out of bone, before becoming metal once again. However, this metal has been stripped back to reveal the bone once more.

After this creative decision was made about Logan, it was completely ignored. After having the metal cut from his claws, it returns again for his final appearances, without any explanation whatsoever as to how this could have happened.

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