A promo for next week's episode of FX's "Legion" appears to confirm a popular fan theory about the identity of the Devil With Yellow Eyes, the powerful being that's lived within, and tormented, David Haller since childhood: Marvel Comics' the Shadow King.

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Labeled as an "Alternate Promo," the 30-second teaser for Episode Seven depicts an exchange between Bill Irwin's Cary Loudermilk and Jemaine Clement's Oliver Bird. "I've been watching this David person and his monster," says Oliver, who's been lost on the astral plane for two decades. "You know what it is -- or should I say who?" Cary clearly states "Amahl Farouk, the Shadow King," a name familiar to X-Men fans.

It's worth noting that the primary promo makes no mention of the Shadow King. However, while the "alternate" version is low-quality, as if it was recorded off a television using a phone, most of the footage and all of the dialogue is new. If it's fake, it's an incredibly good one. Watch the primary promo below, and the alternate version above.

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From the moment the grotesque creature first appeared in David's fractured memories, Marvel Comics fans had suggested it could be the alien Mojo or the ancient mutant Shadow King, likely owing more to physical similarities than anything else. However, with "Legion's" fifth episode, when it was discovered the monster is the consciousness of a powerful mutant that has fed on David's mind since his childhood, it became clear it's the Shadow King, which had manifested at various times as the Devil With Yellow Eyes, Lenny Busker (played by Aubrey Plaza) and even David's memories of his beloved boyhood dog King.

In this week's episode, more pieces were added to the puzzle, as Lenny taunted David, saying, “I knew your father, did you know that? Your real father, the guy that gave you away. I know, boo-hoo. Talk about an asshole; always acting so holy, and then gives away his only son. He thought he could hide you from me, but he was wrong. I found you." If David's father on "Legion" is Charles Xavier, as it is in Marvel Comics lore, then it follows he gave up his son for adoption to try to keep such a powerful mutant out of the hands of the Shadow King.

Airing Wednesdays at 10 p.m. ET/PT on FX, "Legion" stars Dan Stevens, Rachel Keller, Aubrey Plaza, Bill Irwin, Jeremie Harris, Amber Midthunder, Katie Aselton and Jean Smart.