WandaVision: Here's why you didn't see Mephisto or Doctor Strange in the show

WandaVision's showrunner Jac Schaeffer spoke about the absence of characters such as the famed Marvel antagonist Mephisto and the sorcerer supreme, Doctor Strange from the WandaVision plot. While talking about the same, Jac Schaeffer touched upon the lack of the need of an antagonist on par with Thanos in terms of impact and stature by saying that the real "big bad" of the now-concluded series was essentially the grief that Elizabeth Olsen's Wanda Maximoff/Scarlett Witch was dealing with all along. On the subject of the lack of an appearance by Benedict Cumberbatch's Doctor Strange, Schaeffer simply said that the appearance was just one of those theories that were concocted by fans irrespective of what the show promised in reality. The above information has been sourced from ComicBook.com.

Schaeffer on Agatha Harkness' surprise appearance and function in the story:

On the subject of the "bonus" antagonist that viewers got to see in the form of Katherine Hann's Agnes/Agatha Harkness, Schaeffer shared that she felt good about how she essentially ended up playing the part of Wanda's therapist during Episode 8. WandaVision's penultimate chapter saw its titular character looking back at the events that predate the timezone in which WandaVision plot was unfolding, which supposedly helped her overcome most of the trauma that she was theorized to be suppressing since her MCU debut. Details regarding the appearance of Mephisto, should the character ever make an appearance in the eponymous cinematic universe, will be shared with the readers as and when they are made available. All of the episodes of WandaVision can be streamed on Disney+, Disney+ Hotstar, or Hulu, depending on one's geographical location.

About WandaVision:

WandaVision stars Elizabeth Olsen as Wanda Maximoff and Paul Bettany as Vision. Supporting characters include Kathryn Hahn as Agnes/Agatha Harkness and Kat Dennings of 2 Broke Girls fame as Darcy Lewis from Thor: The Dark World. Other actors that were seen on the show include the likes of Even Peters as Ralph Broner, Teyonah Parris as Monica Rambeau, and Randall Park of Always Be My Maybe fame as officer Jimmy Choo. WandaVision finale episode, which reportedly set up future MCU outings, aired on the 5th of March, 2021