The X-Men are coming to the MCU - and the storytelling method behind it may already exist. In December, every Marvel fan's dream finally came true; the House of Mouse and Fox finalized a deal that will see Disney purchase the bulk of 21st Century Fox. As a result, the X-Men film rights are finally returning to Marvel. At least eventually; while the entrance of mutants the cinematic universe is confirmed, the deal has to go before the regulators, and won't be approved before the end of 2018 or, more likely, mid-2019.During that time, there's not going to be any cooperative efforts to bridge that gap. However, both Marvel and Fox have nevertheless begun to invest a lot of time and effort in plot devices that could ultimately combine the two franchises. Could an Avengers/X-Men crossover be easier than people are expecting?The X-Men Franchise Already Has All The Tools For A Reboot (This Page)

The MCU Already Has The Idea Of A Multiverse

Doctor Strange introduced the idea of the "multiverse", a concept that Kevin Feige has noted "is gonna come in handy." In Marvel Comics, the idea is tied to parallel realities that are subtly different to the mainstream timeline. It's been a particularly important concept in Marvel's What If? comics. These would explore the consequences of a hero making different decisions, or a villain emerging triumphant in a key battle. What if Spider-Man joined the Fantastic Four? What if Iron Man lost the superhero Civil War? What if Professor X and Magneto had formed the X-Men together? Ironically, many of these ideas proved intriguing enough for them to ultimately happen in the main Marvel timeline: General Ross first became a Hulk in an issue of What If?, and the series toyed with the idea of Jane Foster becoming Thor too.

RELATED: The History of Marvel's Alternate Universes

Some of Marvel's parallel universes are far more different, though. In one timeline, Wolverine is gay and in a relationship with Hercules. In another, Cyclops is female. In the Ultimate universe, mutants were artificially created by human scientists, and Wolverine was their first creation. It's quite possible that the X-Men films simply explore different realities to the MCU timeline. Meanwhile, the X-Men franchise itself has long embraced the concept of the multiverse; it's why Legion and The Gifted are able to happen, with showrunners Noah Hawley and Matt Nix creating timelines that are already out of sync with anything fans have seen on the big screen.

The most important link, though, is in Guardians of the Galaxy Vol. 2. That film reveals that Stan Lee's cameos are actually appearances by the "Watcher's Informant," a cosmic being who transcends time and space. Significantly, in the comics, the Watchers observe all of reality. One of their number, Uatu, usually introduces the What If? comics. There's no reason the Stan Lee cameos in the X-Men timeline couldn't also be the Watcher's Informant.

The foundation, then, has been laid. The X-Men films could easily be simply a different part of the Marvel multiverse. If that's the case, time-travel plots and reality manipulation could actually bring them together. And there's a lot of them coming.

Deadpool 2 Will Introduce Full-On Time-Traveller Cable

This year's Deadpool 2 will introduce Cable, one of Marvel's most notable time-travelers. In the comics, Cable is the son of Scott Summers and a clone of Jean Grey. Poor Cyclops was forced to send his infant son into the future to save his life. Cable returned as an aged warrior, a powerful cyborg who defends the timeline. Of course, while fans are expecting a comic-book-accurate version of the character's personality, Deadpool 2 is unlikely to explore Cable's complex backstory (although Deadpool is sure to make a quip or two about it) - but it's still there.

Related: Deadpool 2 Can Fix' the X-Men Movie Continuity

Importantly, in October 2017 set photos suggested Cable's time-travel device will be a circular wrist-mounted unit; something rather like a futuristic watch. Although this seems to be little more than a minor detail, it's actually key. Future set photos have shown very similar devices, as we'll see.

The Phoenix Force Will Change The X-Men

X-Men: Dark Phoenix is set to see Sophie Turner's Jean Grey gain access to the cosmic power of the Phoenix Force. While Marvel fans are most familiar with the Phoenix as a cosmic force of death and rebirth, it's actually far more.

In Mike Carey's graphic novel X-Men: No More Humans, for example, the Phoenix Force's power was able to transcend reality. The story saw the Earth's humans shunted into a sort of "dimensional storage," a pocket reality in which time did not exist. It also saw mutant refugees from other realities brought to the main Marvel timeline. In the end, the Phoenix Force was able to put matters right. The humans were brought back out of virtual storage; the Phoenix adjusted reality to ensure no lives were lost due to car and plane crashes. It also, sadly, sent the mutant refugees back to their own realities.

It seems X-Men: Dark Phoenix will be a tad more grounded, but there have been hints that this is only the first film in a two-part story. Dark Phoenix may well be set up for something that is truly cosmic in scope ” and that could well change the nature of reality.

Related: Will X-Men: Dark Phoenix Reboot The Fantastic Four?

Kitty Pryde's Surprise Movie May Be The Key

Kitty Pryde

Perhaps the most unexpected plot device is Kitty Pryde. In the comics, Kitty is a mutant who can phase through solid matter. In the movies, she possesses a very different powerset; she can cast minds back through time and space. Fox has already used Kitty to reboot their timeline once, in X-Men: Days of Future Past, and there's no reason they couldn't do the same again, especially in light of recent reports Tim Miller is working on a Kitty Pryde movie.

The Infinity Gauntlet Could Change Everything in The MCU

The ultimate cosmic power, of course, is the Infinity Gauntlet itself. Avengers: Infinity War will see the Mad Titan head to Earth, pursuing the Infinity Stones. Should he prove successful, Thanos will gain control over all time and space. In the comics, he used the Gauntlet to snuff out half the life in the universe with a snap of his fingers. This, quite obviously, has some serious ramifications.

Interestingly, in 2015 Jonathan Hickman's Secret Wars revealed that each reality has its own Infinity Gauntlet. The Gauntlet of one reality only has limited power when it is used in another dimension, suggesting that even the power of the Reality Gem wouldn't be enough to actually merge dimensions.

Related: Every Marvel Movie Coming in 2018

But would Marvel Studios consider that to be binding? The films are always loosely adapted from the comics, after all, meaning Marvel could choose to take a very different direction. In the MCU, the Gauntlet could be powerful enough to combine different realities. As such, it could easily bring the X-Men into the MCU.

The Multiverse and the Quantum Realm May Lead To A Reset

Ant-Man and the Wasp will also revisit the idea of the Multiverse. The film will see the heroes struggle to rescue Michelle Pfeiffer's Janet Van Dyne from the Quantum Realm. They'll clearly be successful, but in doing so will return to the idea of the Multiverse. According to Evangeline Lilly, the Quantum Realm will open up the opportunity to travel through time and space. "That does open a whole entire new multi-verse to enter into and play around in," she explained in an interview back in November. The Quantum Realm is also confirmed to play a part in Captain Marvel, so it's clear Marvel intend to build on these opportunities.

Time-Travel in Avengers 4 May Rewrite The Timeline

Ant-Man and Doctor Strange with Thanos and the Time Stone in Avengers 4

The evidence is building that the as-yet-untitled Avengers 4 will actually be a time-travel film. With Infinity War directly leading into its sequel, there will likely be a narrative throughline between Ant-Man and the Wasp, Captain Marvel, and Avengers 4. Indeed, the most probable way the heroes could travel through time is via the Quantum Realm.

And this is where things become particularly interesting, care of a new series of set photos from Avengers 4 shows Ant-Man at the time of the Battle of New York. Importantly, many characters are seen wearing strange devices on their hands. They're crude, circular wrist-mounted units that look rather like timepieces. Visually, these units are similar to the one worn by Cable in set photos from Deadpool 2, a fact that has started mass speculation. Whether that's intended as a direct link or not, the fact Marvel and Fox seem to be using time-travel technology that looks similar in appearance is very intriguing indeed.

Related: The Avengers Should Become The Ultimates in Marvel Phase 4

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It's clear that both studios are exploring concepts of time-travel and alternate realities. As such, both Fox and Marvel are setting up a lot of ideas that could easily be used to merge the X-Men and MCU franchises. The question is, is this planned? The nature of the deal would suggest not, although it must be said Fox and Marvel seem to have had a stronger relationship in recent years, even agreeing to a small deal that allowed Marvel to use Ego the Living Planet, while Fox were given permission to redesign Negasonic Teenage Warhead. It's possible that, even before the Disney purchase was on the cards, Marvel and Fox were planning to bring their universes together.

If that is indeed the case, Disney's plans will simply make it far easier for this to happen.

Next: Thanos Is Still The Main Villain In Avengers 4

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