WARNING: The following contains spoilers for WandaVision Episode 9, "The Series Finale," now streaming on Disney+.

WandaVision's emotional ending sees Wanda Maximoff finally beginning to make peace with her grief. A devastating yet hopeful series of events lead her to a quiet, far away cabin. The series finale debunks a lot of fan theories, but there are still potential clues to Wanda's future, even in her last scene. The biggest one is the mountain that overlooks her new home: It very well may be Wundagore Mountain, Wanda's comic book birthplace, and the lair of the Darkhold's horrific author, Chthon.

The reveal of the Darkhold is a major turning point for the franchise. Originally introduced in Agents of S.H.I.E.L.D. as an evil grimoire, the book later appeared in the final season of Runaways. Before Agatha's spell book was confirmed as the Darkhold, theories also suggested that it might have been its counterpart, the Necronomicon. But in the end, it was revealed as a new take on the classic Marvel tome of evil, and now it's in the hands of the Scarlet Witch.

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Wanda's cabin from the WandaVision finale

While the long history of the Darkhold can be confusing, 2009's Mighty Avengers #22, by Dan Slott and Khoi Pham, established there is an ancient fortress deep within Wundagore, part of the fictional Transian mountain range. There, in the ancient days of Earth, the eldritch horror Chthon lived in secret, writing the Darkhold. 2016's Carnage #8 by Gerry Conway and Mike Perkins confirmed that exposure to the tome inevitably corrupts its readers, making them susceptible to Chthon's control.

Chthon was later imprisoned within Wundagore in the 6th century by a sect of magicians dedicated to halting the Elder God's chaotic influence before he took over the world. Although the gate is physical, Chthon is actually trapped between universes and uses his corruptive power and the Darkhold to turn people into puppets driven to release him into reality once more.

Vision and the Scarlet Witch #4
Wundagore Mountain, from Vision and the Scarlet Witch #4

In Avengers #186, by Mark Gruenwald, Steven Grant and David Michelinie, with pencils by John Byrne, Wanda and Pietro Maximoff's origins are revealed. Brought to Wundagore, the twins learn that they were born on that mountain during a struggle between sorcerers and the escaping Chthon. Chthon's was beaten, but when the newborn Wanda entered the world, his chaos marked her, granting her a future as the Scarlet Witch. The issue sees Wanda confronted with the Darkhold, with her ties to the chaotic eldritch god revealed to her at last. For the first time, and unfortunately not the last, Wanda finds herself corrupted and controlled by Chthon himself.

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the Darkhold from the WandaVision finale

The Darkhold may have been among the artifacts young Agatha stole from her coven in colonial Salem, and her powers do share some similarities with the corruptive, soul-draining nature of Chthon. If this is the case, it's likely that Agatha isn't just worried about the Scarlet Witch taking full command of her abilities. Her claims that Wanda doesn't understand what she's unleashed seem to be referring to more than Wanda's own chaos magic. Agatha's newfound fear could be that the Scarlet Witch will fall under the lure of the Darkhold, and by extension, Chthon himself.

With Doctor Strange in the Multiverse of Madness still on the far horizon, Wanda has plenty of time to absorb the dangerous lessons of the Darkhold. If she has in fact recused herself among the beautiful foothills of Wundagore Mountain, she may have no idea how close she is to the danger that's corrupted her comic book counterpart several times before. She could become more than the great witch of prophecy: Wanda may become a vessel of Chthon.

Written by Jac Schaeffer and directed by Matt Shakman, WandaVision stars Elizabeth Olsen as Wanda Maximoff/Scarlet Witch, Paul Bettany as Vision, Randall Park as Agent Jimmy Woo, Kat Dennings as Darcy Lewis, Teyonah Parris as Monica Rambeau and Kathryn Hahn as Agnes.

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