This article contains spoilers for 2021's Thor annual.
Marvel Comics has introduced a new Multiversal threat, one that can even break the Mighty Thor - and it would be perfect for the MCU. The Multiverse is central to the MCU's Phase 4 narrative, and naturally, that means it's becoming increasingly important in the comics as well. Take, for example, 2021's Thor annual, by Aaron Kuder, Cam Smith, Chris O'Halloran, and Joe Sabino. This sees Thor come face-to-face with his darkest incarnation - the God of Blood and Thunder.
In this timeline, the Mighty Thor killed his brother Loki, and was banished from Asgard for his crime. Regret and shame roiled within his heart, gradually transforming into anger and rage, and he became the most unworthy Thor imaginable - striking shocking alliances, and ultimately leading an army back upon Asgard. The Champion of Hela, leader of the Armies of the Dead, the God of Blood and Thunder is truly a force to be reckoned with.
But, in reality, he is only a pawn. An entity has slipped into this dimension from another reality, a being who calls himself Valg. His race literally feeds off chaos and violence, and they grow in power by manipulating the minds of others to cause that. Valg is a scout who slipped into this dimension one particle at a time to arrive on the Realm of Alfheim. Although he was initially dismayed to discover the peaceful Light Elves, Valg was delighted when the War of the Realms broke out. "As far as I can tell, your Realms come with every flavor of chaos and violence," he tells Thor. "I doubt I could have found a better feeding ground in a hundred lifetimes."
Valg is essentially a demon, a corrupting being who possesses others and taints them. Chillingly, he can completely possess a host body; using this, he can disguise his presence with ease, manipulating his way into positions of power and influence in order to cause as much trouble as possible. When he wishes, he can emerge from the host by tearing out of their body like a snake shedding its skin. The creature is a truly malevolent predator, and apparently, there's an entire race of such beings out there, tearing through the Multiverse.
This creature is absolutely perfect for the MCU. Marvel's Loki series launched the Multiverse on Disney+, and you'd expect to see all manner of strange and even sinister forces emerge. What's more, Phase 4 is even embracing the kind of pseudo-horror associated with creatures like Valg, with the Marvel Zombies emerging in Marvel's What If..? Meanwhile, Elizabeth Olsen has suggested Doctor Strange in the Multiverse of Madness will be the scariest Marvel movie. That means Valg really would work well in the MCU's Phase 4 - and it would be thrilling to see this creature facing off against Thor on the big screen.