Fan theories are nothing new when it comes to the Marvel Cinematic Universe, and one recent Reddit fan theory speculates that the MCU will be introducing new symbiotes during the next wave of projects for the franchise. Right now, Marvel heroes are more focused on preserving the multiverse and making sure that the timelines stay balanced, since He Who Remains no longer has a plan for the universe. So, it could be quite some time before symbiotes have a larger impact on the Marvel universe.
With that being said, the theory, posted by user S0UL-LESS, suggests that a lesser known character, Knull, will be coming into play sometime around season 2 of Loki. Knull is the creator of the symbiotes, and he lives in what Marvel Comics calls the primordial void. Technically speaking, Knull the god of the symbiotes, and the Reddit user points out that Knull’s first symbiote, All-Black, killed a Celestial in the comics. After All-Black killed the Celestial, its massive head was used to foster a mining operation in space. This became known as Knowhere, which has been featured in various MCU films.
The first time Marvel introduced Knowhere was in Thor: The Dark World during a mid-credit scene, when Thor’s friends visited the Collector to pass off an Infinity Stone. Later, the severed head became a major location in Guardians of the Galaxy Vol. 1. The Guardians returned to Knowhere during Avengers: Infinity War, where Thanos tortured the Collector and tricked Gamora into thinking she had succeeded in killing her adoptive father. Additionally, the mining hub was shown on a computer screen in episode 2 of Loki, right before the timeline broke.
Given that Knowhere and Celestials exist within the Marvel Cinematic Universe, the theory states, it’s almost undeniable that Knull also exists in the MCU. Marvel often hints at future plot points years in advance, so the recurrence of Knowhere in the MCU certainly wasn’t an accident. It could easily be the setup to a larger, symbiote-centric storyline.
The Venom: Let There Be Carnage post credits scene began a new Marvel/Sony crossover, by establishing that Tom Hardy’s Venom knows Tom Holland’s Spider-Man. Spider-Man: No Way Home continued the crossover with its mid-credits scene, showing Hardy’s Eddie Brock at some sort of bar in the MCU. In the scene, Venom leaves behind a small piece of himself in the Marvel universe before Doctor Strange sends all the outsiders back to their respective universes, which means Venom is technically still lingering in the MCU.
Marvel and Sony have publicly expressed their desire to keep working together, and it seems as if some sort of Venom and Spider-Man storyline is already in the works, if the aforementioned scenes are anything to go by. Between the existence of Celestials in the MCU, the frequent return to Knowhere, and the likelihood that Venom and Spider-Man will one day meet face to face, the foundations have certainly been laid for Knull to pop up at some point in the future.
The Reddit theory says that Knull’s creation, All-Black, took a liking to a version of Loki in the Marvel Comics, who went by the name King Loki. Together, All-Black and King Loki went on a murderous rampage and gave birth to a new race of beasts known as Necro-Ravens.
Fans who watched season 1 of Loki know that a virtually infinite amount of Loki variants exist within the multiverse. The show introduced variants like Classic Loki, Kid Loki, Alligator Loki, and even President Loki, though his time in the series was short-lived. Hiddleston’s Loki currently resides outside the boundaries of time and will likely have more variants to face as he does his best to repair the multiverse and fix the TVA in Season 2.
Assuming that Knull and the symbiotes will be causing chaos down the line, u/S0UL-LESS suspects that All-Black will bond itself to a Loki variant and become one of the main villains in Loki season 2. As of right now, there’s no definitive release date for the next season of Loki, but the show is rumored to start filming mid-2022, so a 2023 release date seems most reasonable. This means that movies like Doctor Strange in the Multiverse of Madness, Thor: Love and Thunder, and possibly even Ant-Man and the Wasp: Quantumania will hit the big screen before Loki returns. All of these projects have the potential to shape the events of Loki Season 2 — especially Ant-Man 3, in which Johnathan Majors will be returning as Kang the Conqueror.
Now that the MCU is regularly introducing new timelines, universes and multiversal conflict, the door has been left wide open for all types of creatures to jump through. There’s still plenty of time for Knull and his symbiotes to appear in new projects, and All-Black just might have something to do with the God of Mischief’s next adventure.