WandaVision episode 8 further cements the idea that the twins Wanda and Pietro Maximoff have been superpowered since birth due to genetics, but the twist that they are basically the MCU's first mutants was spoiled back in 2020, in a book called The Wakanda Files. When they first appeared in the MCU, Wanda and Pietro were described as "miracles," a term the MCU has quietly let fall away. With the appearance of the Evan Peters version of Quicksilver/Pietro, the MCU offers the first onscreen hints of a crossover between the mutants of the X-Men and the "enhanced individuals" of the MCU. Mutants will appear in the MCU at some point, and Marvel seems to be slowly building up to their introduction.

The distinction between characters like the Maximoff twins and other super-powered individuals in the MCU is that they've had their powers (or their latent abilities) since birth; heroes like Steve Rogers, Carol Danvers, and T'Challa were altered or augmented at some point in their lives. Other enhanced individuals like Thor and Gamora are alien beings who aren't human. WandaVision episode 8 suggests that Wanda has had her powers in some form since she was a child – when Agatha realizes the young Wanda used a Probability Hex to prevent the Stark Industries bomb from exploding in the Maximoff living room in Sokovia.

Related: Why Aaron Taylor-Johnson's Pietro Wasn't In Wanda's Memories

But this isn't the first time Marvel has hinted that the Maximoff twins might have had their powers in some form since birth. The book The Wakanda Files, released in 2020 and presented as notes collected by Wakanda's Shuri about the world of the MCU, includes notes about Scarlet Witch and Hydra. The book shows that Hydra settled in Sokovia in order to research genetic anomalies in the people from the country and hoped they would make good test subjects for their experiments with the Mind Stone. Scarlet Witch and Quicksilver were two such Sokovians who became test subjects, and the Stone amplified their already existing powers. This revelation that the twins' powers are genetic in nature classifies them in a similar way to the mutants of the X-Men universe.

Wanda has always been linked to the Mind Stone: through her relationship with Vision, whose life is powered by the stone, and her attempt to destroy the Stone before Thanos could obtain it. Her powers, such as telekinesis and mental manipulation, also link her thematically to it. Episode 8 further binds Scarlet Witch to the Mind Stone as her powers are amplified through exposure to it, solidifying Wanda's status as superpowered by genetics, just like the mutants.

There's been plenty of debate over the best way to introduce the mutants of the X-Men into the MCU. For example, will actors like Ian McKellen and Michael Fassbender play Magneto again, or Hugh Jackman don the claws to play Wolverine? For a long time, it was a non-issue: Disney owned the characters and IP of the Marvel universe, but 21st Century Fox owned the rights to develop films based on the X-Men universe. Though it's not unheard of for studios to collaborate on characters (see the current MCU iteration of Spider-Man) it didn't seem likely that the two would cooperate. Until Disney purchased Fox in 2019, that is. Now, with the rights to Marvel and X-Men characters both sitting with Disney, the barriers to seeing fan-favorite mutants in the MCU have fallen.

Disney and MCU producer Kevin Feige are keeping quiet about how and when characters like Storm, Professor X, and Jean Grey might appear alongside Scarlet Witch and Doctor Strange, but speculation is rife that they may appear at some point in Phase 4. While the version of Pietro who appeared in WandaVision isn't exactly the debut of one of the X-Men, it's an exciting acknowledgment that the two universes are set to collide. Of course, no official MCU property has yet used the word "mutant" to refer to any of the characters in the universe, but the time must be coming close and Marvel is clearly laying the roadwork for the introduction of the X-Men into Marvel Phase 4 or beyond. WandaVision episode 8 was just the latest step in building the universe up to accept mutants in their true form.

More: All 12 Marvel TV Shows Releasing After WandaVision

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