People really want Mephisto to be the big bad ofWandaVision. Even though those chances decrease with each passing episode, the character is continually brought up as a villainous choice in virtually all social circles. So much so, in fact, it has essentially become a meme by now. Now that Evan Peters has joined the series as Pietro, seemingly taking the place of Aaron Taylor-Johnson's character from Age of Ultron, the actor has found himself at the root of most villain-related theories.