Agatha Harkness' magic in WandaVision offered another hint at Chthon, the potential villain of Doctor Strange in the Multiverse of Madness. "It's all connected." Since the launch of the MCU back in 2008, those three words have been both Marvel's mission statement and their promise. The studio has built the most successful shared universe of all time, one in which Asgardian warriors can find themselves going toe-to-toe against cosmic depots, where super-soldiers from the Second World War ally with men in high-tech armor. And somehow it all works.

Phase 4 of the MCU sees the shared universe expand into a series of popular live-action TV shows, which both flow from and set up the movies. WandaVision was the first, transforming Elizabeth Olsen's Wanda Maximoff into the Scarlet Witch ahead of Doctor Strange 2. According to an ancient prophecy, the Scarlet Witch is destined to destroy the world - and WandaVision suggested that may well be because of her mystical connection to the Elder God Chthon. In the comics, Scarlet Witch's Chaos Magic originates from Chthon, and he is the one who first created the book of forbidden magic called the Darkhold.

Related: Theory: Scarlet Witch's Chaos Magic Sets Up Doctor Strange 2's Villain

But WandaVision may well have hinted at Chthon in more ways than just Wanda's identity as the Scarlet Witch and her use of Chaos Magic. Agatha Harkness unveiled what seems to be a formidable weapon against sorcerers: ancient runes that. among other undescribed purposes, if inscribed around the boundaries of an area, prevent any sorcerer other than the one who cast them from using their power. These runes don't correspond with anything seen in the comics, and that may actually be the real point; Marvel's 2016 Carnage series revealed Chthon's magic can also be accessed through the casting or runes, but these were never properly shown in the comics, meaning Marvel Studios would have complete flexibility in designing those from scratch.

Runes Wanda Agatha

Agatha Harkness has clearly possessed the Darkhold for some time, given she knew there was an entire chapter in it dedicated to the Scarlet Witch. That means it's entirely reasonable to imagine she was using runes she had learned from the Darkhold. Indeed, given these runes inhibited even Wanda's Chaos Magic, it makes sense for them to also originate from Chthon. The interesting question is whether these runes would also limit the Masters of the Mystic Arts; if so, Chthon could himself cast them to neutralize even as powerful a sorcerer as Doctor Strange.

WandaVision certainly seems to be setting up the MCU's version of Chthon as the main villain in Doctor Strange in the Multiverse of Madness, and it is doing so by positioning Wanda Maximoff as a force to be reckoned with. It's likely Wanda will have been studying the Darkhold for months (at least) before she encounters Doctor Strange again, which means she could have learned a lot of magical secrets he would wish she didn't know.

More: Phase 4 Makes Doctor Strange The MCU’s Protagonist (Not Scarlet Witch)

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