In WandaVision, Agatha Harkness (Kathryn Hahn) could actually be saving Scarlet Witch (Elizabeth Olsen) from the real villain of Phase 4, Kang the Conqueror (Jonathan Majors). Through most of the series, it seemed that the biggest problem facing the characters in the show was Wanda Maximoff herself, as she was the one who was maintaining telepathic control over the residents of her fake world, Westview. However, WandaVision episode 7 explained that a secret character was pulling the strings.
At the end of the episode, Wanda found out that her friend Agnes was really a sorceress by the name of Agatha Harkness. A musical sequence took viewers back and revealed that Agnes killed Sparky and sent a Quicksilver imposter to fool Wanda. Plus, it looks like Agatha may have done something with Billy and Tommy, as both of Wanda’s children appear to be missing. Agatha hasn’t said what she’s really after, but it’s being theorized that she, being aware of Scarlet Witch’s magical capabilities, could be after her power in order to increase her own.
It should be noted that WandaVision’s big Agatha Harkness reveal is far from a solid confirmation that she’s the show’s main antagonist. It wouldn’t be a stretch to believe that she’s allied with Nightmare or Mephisto, as either fits the criteria for Doctor Strange in the Multiverse of Madness’ villain. Alternatively, it could be that Agatha isn’t a villain at all. Instead, she could there to prevent Wanda from going down a darker path.
The words “it was Agatha all along” certainly give the impression that she’s WandaVision’s main antagonist, but this could all be one big misdirect. While it could be true that Agatha is responsible for Sparky’s untimely death, a fake Quicksilver coming to Westview, and Vision finding out the truth, none of these things necessarily mean that Agatha is evil. What they do mean, though, is that Agatha has a vested interest in Wanda’s life. In trying to decipher Agatha’s real role in WandaVision, her comic book history could be the key to finding the answer. In Marvel Comics, Agatha is an experienced sorceress who lived through the Salem Witch Trials. She’s also Wanda’s mentor and a character who has helped her through numerous challenges that were magical in nature. Based on past MCU stories, it wouldn’t come as a huge shock if Marvel changed Agatha into a villain in WandaVision, but it may be that the series is tricking viewers for the time being.
Her actions thus far may be indicative of her true plan. The results she has gotten show that she may be trying to tear down Wanda’s fake world. The things Agatha has done has caused chaos in Westview and problems for Wanda. Vision figuring out what’s really going on has made carrying on as normal increasingly difficult for Wanda. It may be that Agatha knows Wanda is more powerful than her, so she’s avoiding a direct confrontation. Instead, she could have been trying to get to Vision and doing other things that can wear on Wanda’s psyche. If Wanda is misusing her magical abilities, she could be a threat to the Earth and perhaps the fabric of reality itself. Agatha may believe that destroying Westview is what’s best for the world. As for the boys, whatever she’s done to them may not be an act she perceives as morally wrong, considering that both are just manifestations of Wanda’s power.
Agatha may not be the only MCU character who has set their sights on Scarlet Witch in WandaVision. There’s also Kang the Conqueror, who is confirmed to appear in Ant-Man and the Wasp: Quantumania, presumably as the villain. Kang is known for being a time-travelling villain from the future who tangles with the Avengers and the Fantastic Four. In Marvel Comics, both Kang and Scarlet Witch are “nexus beings”, people capable of affecting the timestream. WandaVision’s Nexus commercial teased this might be the case in the MCU, at least for Wanda, and given the nature of Kang’s character, his MCU counterpart would likely be one as well. As a character who is believed to be Phase 4’s main villain, it would make sense for Kang to be connected to WandaVision in some way. After all, Kang is deeply connected to time and the multiverse, which is confirmed to be key to Scarlet Witch’s next MCU story, which will play out in Doctor Strange 2.
Then there’s the matter of Scarlet Witch and Kang’s comic book connection. In the pages of West Coast Avengers in the 1980s, Immortus (an alternate timeline version of Kang) used time travel to secretly manipulate events in Wanda’s life. That’s because he was aware of the depths of her power and was convinced that if he possessed them, he could become even more powerful. He knew that Scarlet Witch’s abilities would help him create and control new timelines and realities. For this reason, Immortus operated behind the scenes to engineer Scarlet Witch’s mental and emotional breakdown. Among the tragedies he caused was Vision’s destruction, as he knew he’d be rebuilt without his emotions, which would only add to Wanda’s heartache. His plan from the beginning was to gain access to her powers and become a time master. It could be that the MCU’s Kang the Conqueror (or Immortus) shares the same plan.
If Kang is the one who’s really behind all of this, it may be that he’s playing the long game. He could be slowly draining Wanda of her power without her knowing it, which would tie into the fact that Wanda sometimes struggles to make things disappear or control her constantly-changing environment. It’s also possible he may be trying to weaken her until he can somehow take her abilities. The point of Agatha’s efforts against Scarlet Witch in WandaVision could be to put an to end this before it gets that far.
Agatha having this plan would be right in line with what is known about the comic character. In the same story that saw Immortus try to take Wanda’s powers, it was Agatha Harkness who stood in in his way. His failure to foresee her role contributed to his eventual defeat. So while Agatha may look like the bad guy of the story, she could instead be an ally. Being a powerful sorceress, she may be the only person who can help Wanda if it’s true that Kang has designs on her powers. Whether or not Agatha can stop him may determine what comes next for Scarlet Witch in Doctor Strange 2, and what direction Marvel may take Kang the Conqueror in Ant-Man 3 and potentially Avengers 5.