WandaVision is filled to the brim with references to the Marvel Cinematic Universe. "A Very Special Episode," the show's fifth installment included a major Easter egg to another movie franchise: the Fox X-Men series. With the introduction of Evan Peters' Quicksilver into the series, the MCU is changed forever.

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Though a lot of questions remain about what is going on in Westview, it's clear that the door has been swung open to alternate realities, in the form of previous Marvel movies, that will allow characters to cross over in ways that will have big and small impacts on the MCU.

Opens Door To The Multiverse

Doctor Strange in the Multiverse of Madness

The biggest and most obvious change is the introduction of the multiverse. This has been teased with the upcoming Doctor Strange In The Multiverse of Madness, in which Wanda will appear, and also the third Spider-Man MCU movie.

In that movie, it's expected that Alfred Molina will reprise his role as the iconic Doctor Octopus from the 2004 Sami Raimi Spider-Man 2 and Jamie Foxx will return as Electro from the Amazing Spider-Man 2. How those two villains will fit into the MCU likely has a lot to do with what is going on with Quicksilver.

Other X-Men Could Appear

Quicksilver Evan Peters WandaVision X-Men MCU SR

With Evan Peters now part of the MCU, it's now possible that other major characters from the previous X-Men films could show up. They don't necessarily have to have a connection to Wanda, as Pietro does (although Magneto, in particular, has a powerful connection to both).

With different Spider-Man villains showing up, and maybe even different Spider-Men, then it's likely that Wanda opens the door to characters like Wolverine, Storm, and Deadpool as well.

Retconning Wanda's Origin

Magneto and Scarlet Witch

Because of the complicated issue of who held the rights to mutants Scarlet Witch and Quicksilver, the MCU versions retconned their origins to fit into the movies. That eliminated Magneto as their father, which had been something of an ongoing affair in the comics.

He wasn't originally their father, and then in the 80s, retconned into it. Recently, thanks to the movie rights issues, the comics changed it again so he wasn't. But with the characters all back under one roof now at Disney, could Wanda alter her origin as she has altered the reality of Westview?

Potential Brotherhood Of Evil Mutants

Magneto, Toad, Scarlet Witch, Quicksilver, and Mastermind during the Brotherhood's first appearance.

If Wanda were to bring Magneto into the MCU as well, that could lead to the introduction of a major Marvel team of villains. Wanda originally debuted alongside her brother in Uncanny X-Men #4 in March 1964 as a member of the Brotherhood of Evil Mutants.

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It's possible that Quicksilver's arrival in the MCU could be the spark that ignites this team into being. Wanda could even wear her original green costume and unusual face-framing mask, never seen again after these early issues.

Someone Else Is In Control In Westview

WandaVision Episode 5 - Agnes Babysitting

Wanda very clearly states to Vision in episode five that she isn't responsible for Quicksilver showing up. That's clear in her reaction. That suggests then that someone is, and someone else is in charge of what happens in Westview. Is it Agnes, who knows something about what's going on? Her husband, Ralph? WandaVision is also built on references to vintage TV shows. One of the biggest sitcom tropes the show employs is the unseen character, often referred to but never appearing. Could Ralph be the hidden force in Westview?

Could Drive Wanda Over The Edge

Scarlet Witch vs Thanos in Avengers Endgame

Wanda is already in a fragile state. She is suffering from grief, trauma, and PTSD over the losses of her brother and Vision. Pietro's return might seem to ease her pain some, but it also stands to make it worse.

He's not really her brother and her confusion over what is real and what isn't could lead to reality further eroding in Westview and even beyond. If it's a trick, as could be the case, her hurt and anger could easily send her over the edge and Wanda could lash out in terrifying ways.

Two Quicksilvers

Evan Peters as Quicksilver in WandaVision and Aaron Taylor-Johnson in Avengers Age of Ultron

The possibility remains that both Quicksilvers could exist within the MCU. Just as many non-MCU movies could appear in future movies, different versions of Quicksilver could. There is nothing to stop Aaron Taylor-Johnson from returning to the role, from another reality where he never died or by time travel.

Having the two appear alongside each other could lead to some interesting stories, especially as Quicksilver traditionally swings back and forth between being a hero and a villain.

The Inhumans

Inhumans

Quicksilver has a major connection in the comics to the Inhumans through the character of Crystal, who was once his wife. The Inhumans were a victim of the Disney/Fox conflict as they battled it out over movie rights. The team was elevated in the comics and, then, into the short-lived television show to more or less replace the X-Men.

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With the Fox sale complete, there is no need and the MCU can take another shot at the Inhumans by introducing them via Quicksilver. Crystal is one of the most powerful female Marvel characters and would be a great addition to the franchise.

House Of M (Kind Of)

Scarlet Witch disintegrating from cover of House of M Marvel Comic

House Of M is a seminal Marvel comic that inspired some parts of WandaVision. While the circumstances are very different, the core issue is the same: Wanda is in grief over her family. In the comic, she breaks down after realizing her children aren't real.

That is potentially something that could happen in Westview, as it's not clear if Thomas and Billy are figments of her imagination or a product of the strange reality of Westview. As with Quicksilver, if the twins aren't real, then Wanda could suffer even more.

Zodiac

Zodiac Marvel

Another Marvel team Quicksilver could help introduce is the Zodiac. This team is much more obscure than the Inhumans, but several iterations of the group fought the Avengers in the 70s and 80s. The second version of the team was led by Quicksilver while he was briefly a villain again. The second team is ultimately revealed to be androids, and specifically Life Model Decoys. As fans of Agents of S.H.I.E.L.D., L.M.D.s played a vital part in the fourth season plot.

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