The X-Men films are not known for their solid continuity. Many of the films have featured plot inconsistencies, from events not lining up correctly, to people having hair one moment to no hair the next -- chronologically, anyway. So little makes sense about the X-Men canon that, even after the whole thing got rebooted with X-Men Days of Future Past, the only solution seems to let the MCU handle things.
But as we near Dark Phoenix and thus the end of this X-Men continuity, it seems fair to reflect on a franchise that, while entertaining, never found a plot thread it didn't feel like twisting apart by the twain. It's time to ask "How many times did the X-Men films break continuity?"
11. What Aren't Continuity Errors
As these are often thrown around as plot continuity errors, it is important to rationalize the following are not plot errors.
"Why is Professor X alive in The Wolverine?" End of X-Men: The Last Stand, he transfers his consciousness into another body. We don't see what happens between those two points, but that isn't an issue.
"Why does Magneto have powers in the future despite losing them in X3?" The cure fades away. Again, see the end of X3.
"If Sabretooth and Wolverine are brothers, then why doesn't he say anything in the first X-Men film?" He doesn't have to. The lack of overt familiarity between them doesn't mean anything.
"Why don't the characters age realistically?" Because it's a movie.
Those are a few common ones. But now we've got that out of the way, we can dig a little deeper.
10. "I've Never Seen Anything Like This Before...?"
In the first X-Men film, Professor X takes an x-ray of Logan's body, seeing his entire skeleton is laced with adamantium. He claims to have never seen anything like this before.
However. However. Even one film later, it turns out that, nah, that genuine sounding shock from Professor X? All a lie. He knew all along not only where Wolverine got his adamantium skeleton, but who put it on him. In fact, so did Cyclops, who also expresses shock seeing Wolverine's skeleton, since, it turns out, as revealed in X-Men Origins: Wolverine, he was there in the same lab and met Wolverine as a kid.
9. Bolivar Trask -- What?
In the X-Men film continuity, there are two very different versions of Bolivar Trask. There is the Bolivar Trask from X-Men Days of Future Past, as played by Peter Dinklage, and there is the Bolivar Trask from X-Men 3, as played by Bill Duke. Both of them are incredibly different characters, from their appearance, position in the government, and even ages.
And yet, even by the most forgiving standards, even if we accept that they just cast a different actor to play the same character, this makes no sense. Mystique kills Bolivar in the original continuity, which means there is no way Bolivar Trask could live long enough to be played by a different actor.
8. When Is Jubilee?
There are many mutants who appear across the timeline in ways that would break continuity under ordinary circumstances. One of the more jarring examples is that of Jubilee, who, as it turns out, exists as a student of the X-Mansion across a ton of different films.
While she technically appears in the first film, in X2, Jubilee is name-dropped as a student captured by Stryker. Yet, in X-Men Apocalypse, she appears as a student as well, despite the fact that X-Men Apocalypse takes place at minimum 20 years earlier in the continuity. Even the time-traveling shenanigans can't explain that.
On top of that, the same thing happens with Angel, who was a child in the 80s in X3, yet appears as a fully grown man in X-Men Apocalypse. Time travel can't change that much in the continuity.
7. Who Built Cerebro?
This is a well-known break in the X-Men film continuity, but in the first X-Men film, Professor X claims that Magneto would know how to block out Cerebro because he helped build the machine. This is why he wears a helmet, which, in the first film, completely takes Xavier by surprise.
Enter X-Men First Class, a film that precedes the X-Men time travel retcon, where it turns out that neither Xavier or Magneto really made Cerebro. Hank McCoy did. At least, he made the original design. And none of the events of that film were fixed by the time travel shenanigans. Xavier was just a liar.
6. The Immortal Moira MacTaggart
Moira MacTaggart is the CIA Agent from both X-Men First Class and X-Men Apocalypse, who, despite twenty years passing between each film, looks barely five years older. She is clearly American, clearly a government official, and certainly not an Irish scientist like she is in the comics.
Except the X-Men films broke continuity -- again. In X3, Moira MacTaggart appears far more in-line with her original appearance in the comics. Irish. A scientist. And certainly not as old as Professor X. This break in continuity is so drastic that it even blows out the Jubilee one out of the water. Though it is outdone by...
5. Emma Frost
So Emma Frost dies before any time travel takes place.
Emma Frost is shown to be a grown woman in X-Men First Class, only to appear as a teenager experimented on by William Stryker in X-Men Origins: Wolverine. Okay, that's a de-aging continuity break. It isn't like that's even the first time that's happened in the X-Men continuity. But wait -- X-Men Days of Future Past reveals that Bolivar Trask killed Emma Frost -- along with a lot of other X-Men -- between First Class and Days of Future Past.
Now, it would be easy to assume the girl in X-Men Origins: Wolverine with the diamond skin isn't the same Emma Frost as seen in First Class, but William Stryker acts as if this is some remarkably unique mutation, which means he couldn't have seen anything like it before. Which is bizarre considering Stryker worked with Bolivar Trask on the Sentinel project, which means he would've been witness to the experimentation on Emma Frost, and, even if he wasn't, would've been informed about it.
4. How Does Deadpool Even Exist?
Deadpool is a walking continuity contradiction.
But it's important to note a few things about Deadpool. It makes sense that the time travel would keep Wade Wilson from being turned into...that thing from X-Men Origins: Wolverine. However, that doesn't explain his mutant powers in that film.
Wade on a mutant task force organized by William Stryker. He clearly demonstrates mutant powers before even being experimented on with his super fast, bullet-splitting swordplay. He is not a normal human as he is in Deadpool. He's a mutant. And that couldn't be altered by time travel because Wade Wilson was born before the time travel shenanigans happened.
3. The Juggernaut
The Juggernaut is a recent example of the broken continuity of the X-Men films, starting up in the very popular Deadpool 2. In X3, the Juggernaut is a strong looking mutant whose powers, while mighty, are oddly enough overshadowed by one Kitty Pryde. He is also British, but, considering Colossus is American in this film and Russian in the Deadpool films, nationalities aren't a huge example of the X-Men films' broken continuity.
What is an example of broken continuity is the Juggernaut's appearance. In Deadpool 2, the Juggernaut becomes a titanic mass of muscle. Did time travel really alter this character THAT much?
2. Magneto Picking Up Jean
Another big one right here caused by X-Men First Class. In X3, Magneto and Professor X come to pick up Jean Grey personally from her home. They are seen to still be friends and assembling their School for the Gifted together. This happens fifteen years prior to X3.
However, in First Class, which takes place in the '60s, Xavier and Magneto are not on speaking terms after Magneto breaks his spine with a stray bullet. Which means Xavier and Magneto were certainly not together. In fact, Magneto may have been still in his underground prison around the time Jean Grey needed to be picked up, which was far more than 20 years before X3 considering X-Men Apocalypse, which features Jean as a student, takes place in the early 80s.
1. Professor X's Hair And Back
This is perhaps the most glaring issue in the entire X-Men continuity. Professor X is shown without hair as early as X-Men Origins: Wolverine. He is shown walking, bald, but in full control of his powers. This is also the case in X3.
However, Professor X lost his ability to walk in the '60s (First Class), regained it at the price of his powers (Days of Future Past), but didn't lose his hair until facing Apocalypse. However, X-Men Apocalypse only happens because of the time traveling effects of Days of Future Past, which means that the event that triggered Xavier's hair loss in the '80s could never have happened in the original timeline at all.
The X-Men film continuity is broken.