While the Marvel Cinematic Universe does not follow the comics to an exact letter, the MCU undoubtedly takes inspiration from the comics. Redwing is not an actual bird that Falcon communicates with, but it is a mechanical bird that he controls. Black Widow did not betray the Avengers in the MCU, though her relationship with the team in the comics is ambiguous at best. Needless to say, there are certain liberties taken when the MCU adopts from the source material. With that in mind, it stands to reason that where Wanda Maximoff in the comics was the reason mutants vanished the MCU’s Scarlet Witch is going to be the reason mutants join this shared universe over the course of WandaVision and Doctor Strange 2.
In the comics, Wanda Maximoff was trained by an actual witch named Agatha Harkness, who is set to be played by the criminally underrated Kathryn Hahn in WandaVision. Agatha is the Morpheus to Wanda’s Neo and she shows her how to unlock the true strength of her powers. With the ever-expanding MCU set to embrace the more supernatural elements of the comics (Doctor Strange has already been introduced, and Moon Knight, Ghost Rider, and Blade have all either been announced or teased by Kevin Feige and that’s before we even get to the multiverse shenanigans that would need to occur to make Jared Leto’s Morbius interacting with Tom Holland’s Spider Man a logical reality), it stands to reason that the MCU takes those first steps with their Witch, Wanda, and an actual witch in Agatha. With casting calls being put out for Wanda and Vision’s twins Wiccan and Speed, one need not speculate very far as to what could be the cause of Wanda’s potential mental break. In the comics, Wiccan’s powers very much resemble his mother’s, while Speed’s powers resemble his uncle Quicksilver’s powers. At the end of Winter Soldier, Baron Van Strucker said that Quicksilver and Scarlet Witch represented the Age of Miracles. I can think of a different M word that one could use in the 1950s, the rumored Scarlet Witch setting, if they saw two kids running really fast and warping reality. Imagine if, in 1950, a devastated Scarlet Witch utters the words “More Mutants” because she wishes that someone could’ve protected her children after Agatha was responsible for taking them away.
Wanda’s nightmare, indeed.
The MCU’s Scarlet Witch losing her children after she lost her twin brother, her partner Vision right in front of her after being forced to kill him herself, turned to ash herself by the Mad Titan, and then resurrected only to be robbed of her vengeance is undoubtedly enough to push her over the edge. Feige has already said that, entering Phase Four, Wanda is the most powerful character they have. Throw in Wanda’s presence in Doctor Strange 2, existing in one universe where she has to potentially deal with The Wasp jokingly mocking Wanda’s desire to be a mother after having that reality brutally ripped away by Agatha. You can clearly see a scenario where losing her children leads her to not only bring the mutants from another universe into the main MCU universe due to the sheer loss she has experienced, but also leads to the Sorcerer Supreme to have to intervene to eventually put the Scarlet Witch down like in the House of M comic. This becomes even more likely when Wanda realizes that the reason Thanos was able to turn back time and kill Vision in front of her, and ergo rob her of the future she thought they’d have, is because Doctor Strange gave up the Time Stone.
With a new Doctor Strange synopsis being released, and a new director being brought in (three cheers for Jordan Peele being the one who takes the helm), Strange’s continued study of the now gone Time Stone has been teased. Mordo’s decision to eradicate the world of sorcerers could bring him into contact with Wanda Maximoff. Could Mordo be in cahoots with another villain, one that has been here for hundreds of years, and who the Scarlet Witch has an extended history with? And could her past interaction be the reason mutants will now exist in the MCU?
Time will tell.