Back in 2019, Spiderman: Far From Home was released in theatres as the first film to follow up the top-grossing film of all time Avengers: Endgame. In desperate need of a summer vacation, Peter Parker went on a tour of Europe and found himself facing off against Mysterio, who claimed to be from a different reality.

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Although this turned out to be a lie in his mischievous plan, the first mention of the multiverse inside the MCU definitely got fans excited. Doctor Strange: In The Multiverse Of Madness and Spiderman 3 are both set to explore the multiverse in more detail as will the entire future of the Marvel universe. From introducing the X-Men to bringing back fallen heroes, the possibilities could be endless.

10 Merging With The X-Men Universe

scarlet witch quicksilver

Disney's purchase of 20th Century Fox got plenty of fans excited at the prospect of seeing characters like Thor and Spiderman from the Avengers, or maybe even the Guardians Of The Galaxy, teaming up with Professor X and the rest of the X-Men, and since that surprise cameo in WandaVision, the crossover could be right around the corner.

WandaVision saw Evan Peters' Pietro Maximoff, aka Quicksilver, being introduced into the MCU despite his previous role in Fox's version of the X-Men. Although the true origins of Pietro's character in the show are still up in the air, the multiverse is a clear and obvious explanation as to why fans haven't heard of the mutants before while still keeping the beloved actors in the same roles.

9 Into The Spider-Verse

into the spider-verse

In 2018, Sony made a hit animated movie Spider-Man: Into the Spider-Verse, which was one of the first superhero movies to show heroes from multiple realities and traveling between alternate universes. Rumor has it that Tom Holland's third Spider-Man movie could follow in Sony's footsteps and see Holland crossover with other versions of the web-slinger.

Andrew Garfield and Tobey Maguire have been rumored to have roles in the upcoming Marvel movie, and this could just be the beginning.  Bringing back villains like Electro and Doctor Octopus, or even the possibility of Parker teaming up with Tom Hardy's Venom makes the prospect of a Spider-Verse mouth-watering.

8 Could S.H.I.E.L.D Be Replaced By A.R.M.O.R?

WandaVision - Monica Rambeau and Jimmy Woo

Since its collapse in Captain America: The Winter Soldier, S.H.I.E.L.D hasn't been able to recover from the Hydra infiltration and since has seen Nick Fury even leave for outer space in what is presumably S.W.O.R.D base. Fans have seen more of S.W.O.R.D in WandaVision and found out about its formation by Maria Rambeau.

In the comics, S.H.I.E.L.D has two sister organizations S.W.O.R.D and A.R.M.O.R. The latter stands for Altered-Reality Monitoring and Operational Response and is designed to defend the Earth against alternate reality threats, which if the multiverse is really about to be introduced, would be the perfect new organization to introduce.

7 Bringing Back Characters From The Dead

Old Steve Rogers in Avengers: Endgame

It has become incredibly popular for superheroes and villains to be revived and brought back in the Marvel comics, so it's not a massive stretch to say the big-screen versions of the characters could follow the same suit. One main problem is of course undermining the deaths of beloved characters by bringing them back, but with the multiverse in play, things could be different.

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Rather than merely bringing characters back from the dead, Marvel could show us different versions of the hero from other realities. Fans could see a Hydra agent version of Captain America or the various versions of Spider-Man like Miles Morales and Spider-Gwen. The prospect of seeing the fallen heroes one more time will definitely be a thing for the future.

6 Opening The Door For Ryan Reynolds' MCU Introduction

Deadpool With Hugh Jackman Mask Stapled On

Ryan Reynold's Deadpool franchise is one of the biggest superhero hits of all time. As one of the first-ever R-rated superhero movies and its hilarious jokes, the franchise is so unique and untouchable that Kevin Feige has already said Marvel will not re-cast or change the style of the film.

So how will he be introduced? Has he been in the MCU the entire time? This seems unlikely. In fact, the easiest possible explanation is that Deadpool was roaming around and breaking the fourth wall in another alternate dimension, and somehow due to the events in Doctor Strange: In The Multiverse of Madness or WandaVision breaks into the well-known MCU.

5 Bigger Threats From Other Realities?

galactus

After watching the trailers and from the movie itself, fans initially thought Quentin Beck, aka Mysterio, was from another dimension in the multiverse, in fact even Peter Parker believed him enough to hand over Stark's E.D.I.T.H glasses. Although this turned out to be a big disappointment, it did make fans wonder what kind of threats could be out there in the multiverse.

RELATED: Multiverse Of Madness: Marvel Comics' 5 Best & 5 Worst Alternate Dimensions

The multiverse could introduce massive villains like Dr. Doom, Galactus, or Kang the Conquerer, villains which are worthy of taking over the mantle left by Thanos as the biggest threat the Avengers have ever faced.

4 Are Reality-Hopping Adventures About To Become The Next Big Marvel Thing?

Owen Wilson & Tom Hiddleston in Loki

When fans saw that Loki was able to escape from S.H.I.E.L.D with the tesseract in Avengers: Endgame, everyone wanted to know where he went and what the God Of Mischief was going to be up to. Loki is now set to star in his very own Disney+ show where fans can watch his adventures after that tesseract teleportation.

In the trailers, Loki is shown to be working with the Time Variance Authority who is responsible for making sure the Marvel universe timeline stays intact. The show should see him cross multiple timelines and realities and could set up a future where more and more characters are crossing over these dimensions.

3 Maybe We Haven't Seen The Last Of The Infinity Stones

Avengers: Endgame

In Avengers: Endgame when all hope was lost, the team pulled together and managed to create their own infinity gauntlet using stones from multiple timelines from their past. By the end of the movie, Steve Rodgers, aka Captain America, went on a mission to return the stones back to the place and time they took them.

But the possibility of heroes or villains using infinity stones from other dimensions is now completely possible and it would actually be surprising if something like that didn't happen again in the future given how powerful the stones are.

2 Not Only Could Heroes Crossover To Other Dimensions, But They Could Also Create Them

Wanda in WandaVision

Scarlet Witch's powers have been limited so far in the MCU. She's mind-controlled all of the Avengers and almost single-handedly took down Thanos in Avengers: Endgame, but her true power is finally being shown in her new Disney+ show WandaVision. In the House Of M-inspired storyline, it's clear that Wanda is extremely powerful and some way or another is creating an alternate reality.

In the comics, Wanda is also a Nexus being, which means she can travel and affect all realities. In her Westview sitcom town, Wanda has revived Vision, had children, and mind-controlled thousands of people as they all act out in her very own sitcoms. Just imagine how crazy alternate realities could get.

1 Are The Fantastic Four Coming?

spider-man x fantastic four in a battle

Kevin Feige has confirmed that a Fantastic Four movie directed by Jon Watts is coming to the MCU and fans are extremely excited. Their introduction, however, is still up in the air just like the X-Men. Reed Richards, Invisible Woman, Human Torch, and The Thing have had an unlucky past with their previous movies, and now Marvel has the chance to redeem the incredibly popular superhero team.

The multiverse is once again the perfect way for them to catapult themselves into the MCU, perhaps enabling Marvel to skip the overly done origin story, like what they did with Spiderman, and head straight into the action.

NEXT: 10 Ways The Snap Fundamentally Changed The MCU