A Spider-Man: No Way Home theory suggests Scarlet Witch was behind sending the Sinister Six villains to Earth-616. In No Way Home, Doctor Strange's memory-erasing spell, which was meant to make everyone forget that Spider-Man is Peter Parker, is interrupted by Peter enough times that the spell gets out of hand. The movie suggests this is what caused Strange to accidentally bring villains from the other non-MCU Spider-Man movies to the main universe.
However, the logic of that premise doesn't exactly make a lot of sense, especially with everything the audience learns about the multiverse in Doctor Strange in the Multiverse of Madness. So, other than Doctor Strange's spell going wrong, bringing, very specifically, Spider-Man villains into the MCU, what is another good explanation for why they suddenly appeared on Earth-616?
Related: Is Doctor Strange 2 A Better MCU Multiverse Movie Than No Way Home?
One Reddit theory outlines the possibility that Scarlet Witch sent the villains to hunt down America Chavez, as part of her plan seen in Doctor Strange in the Multiverse of Madness. This is possible because, per the MCU's timeline, Wanda Maximoff was already the Scarlet Witch during the events of Spider-Man: No Way Home. Through her research into the Darkhold at the end of WandaVision, she is bound to have tested various spells and ways to either bring back her children or to find a universe in which she could be with them. During that testing phase, it's only logical she would practice with lower-powered beings like the villains in No Way Home. This theory claims that this may have been Scarlet Witch's first foray into using other-dimensional figures to try to capture America Chavez. However, in this case, Scarlet Witch
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