WandaVision spoilers follow. Now that WandaVision is over, Marvel is finally opening up to the deluge of fan theories that have followed every episode of the Disney Plus TV show. Head writer Jac Schaeffer has now responded to some of them, explaining that the show's true antagonist is Wanda's grief. The writer admitted that she was affected by the number of theories that circulated, but she was convinced that it was the right approach for the series. "But as far as the total sum of the series, I didn't want to break any promises, and I don't think we ever promised a big bad boy," Schaeffer told THR. "It's based on the fact that the ultimate antagonist of the show is Grief, and that Agatha is the external antagonist. "As far as these theories go, I got a little nervous, but even at this point, I don't want Mephisto or to Magneto. As a viewer, that's not what I want from this series." Whether intentionally or not, WandaVision's absence of an obvious villain hiding in plain sight has opened the door for theories about Mephisto, who is essentially the devil's version of Marvel Comics. Meanwhile, X-Men villain Magneto has been Wanda's father in many Marvel comics. Still, Agatha Harkness felt like the perfect fit for this type of show, and pitching the idea from the Scarlet Witch seemed like enough Marvel lore for a TV show.