Evil Captain America And 6 More Avengers: Doomsday Theories Fans Are Pulling From The Trailer

The first official Avengers: Doomsday trailer is deliberately vague about what’s going on in the MCU’s next big crossover movie, but when has miniscule information ever stopped the Marvel community from speculating? Not once. What theories are the MCU diehards spinning based on the two-and-a-half-minute trailer? None of these have been confirmed, but they may end up happening, so only scroll down if you don’t mind going into the movie with some preconceived notions rattling around in your head. Let’s dive in.

The heroes will lose

There’s a pretty strong basis to the theory that Doctor Doom will emerge victorious at the end of Doomsday. Obviously with Robert Downey Jr. set to reprise the role in Secret Wars in 2027, even those who don’t pay attention to the comics can probably put two and two together and assume that the Avengers and company are going to be facing him again in the next movie. The premise of the Secret Wars comic is that the multiverse is deconstructed and reconstructed by Doctor Doom into one planet called Battleworld, and in order for him to do that, he will likely have to succeed with whatever he’s doing in Doomsday. Looking at the actual comic storyline, it actually helps explain why some MCU heroes might not be around in Doomsday, as they play a large role in the Secret Wars comics, and thus would need to be out of Doom’s line of fire for the movie. Speaking of…

Where are so many of the missing heroes?

Doomsday’s trailer shows dozens of characters from across the Marvel Cinematic Universe converging to fight Doctor Doom, but there are still a lot of folks unaccounted for in the footage and also in the movie’s official casting announcements. With a threat this big, you’d think it would be an all-hands-on-deck moment for characters like Captain Marvel, Star-Lord, Spider-Man, and Doctor Strange to join in on the fight. But fans are speculating that they’ll be part of whatever reinforcements the teams will call upon in Secret Wars, as they all are part of the surviving team in the Secret Wars comic. So how might Doomsday explain their absences? 

“I mean, they’re called the Guardians of the Galaxy not the Guardians of Earth,” a redditor writes. “This ultimately has nothing to do with them since it’s mostly an Earth problem. The only reason they helped out in Infinity War and Endgame was because the whole Galaxy was at stake and they got pulled in by the Asgardians (thinking there might have been money to be made from the attack on their ship).”

Doctor Strange, meanwhile, hasn’t been seen since Doctor Strange in the Multiverse of Madness, in which he hopped into the Dark Dimension with Clea (Charlize Theron) in one of the most disorienting mid-credits scenes the MCU has ever spat out. This does mean he is probably preoccupied with supernatural otherworldly nonsense, but given the two’s romantic relationship in the comics, theories as to what they’re doing instead of helping with Doctor Doom are pretty one-note.

“[Strange is] Sleeping with Charlize Theron in the Dark Dimension,” a redditor speculates.

All right, let’s wrap that up, folks. Spider-Man, meanwhile, is getting his own movie next week with Spider-Man: Brand New Day, so we’ll probably get a sense of why he’s not taking part in the fight in that film.

But there are probably characters that haven’t been announced that we’ll still see in Doomsday

After Marvel kept the secret of Tobey Macguire and Andrew Garfield reprising their roles as Spider-Man(s) in No Way Home right up until the movie’s release, it’s entirely possible Doomsday will somehow squeeze in characters who haven’t been in the trailer or casting announcements. Some fans are even speculating that the Doomsday trailer is made up entirely of footage from the first half of the nearly three-hour movie, and that we’ll see more characters Marvel is keeping close to its chest in the actual film.

What if some characters have been edited out of scenes?

Speaking of No Way Home, before the film was released, fans suspected that the other Spider-Men were in the film based on trailer shots that seemed to have a lot of odd dead space where the other characters might have been edited out. Doomsday has some shots that look just as odd, and while it’s easy to chalk this up to the Marvel movies just kinda looking like shit as they greenscreen dozens of actors with conflicting schedules into scenes together, there is a pretty odd gap in the middle of the room when Thor is giving the crew a pep talk.

What if that’s not the Steve Rogers we know and love?

A lot of Marvel’s promo for this film has focused on bringing back Chris Evans as the original Captain America, but some fans are wondering if the Steve Rogers we see in the trailer might not be him at all. Fans are wondering if this might be Captain Hydra, a multiverse variant of Steve who follows Hydra, the fascist terrorist organization Steve usually fights against, who could be aligned with Doctor Doom in some way. Though the fact that he is deemed worthy of holding Thor’s hammer seems to be an attempt to “verify” to viewers that this is good Steve being dragged out of retirement, Captain Hydra also is able to wield the weapon in the comics. So even that’s not guaranteed.

Another theory I saw that feels a bit roundabout is that this might be Loki or Doctor Doom disguised as Steve, and that the trailer has been edited to mask this. The theorycrafter specifically points to Thor’s awestruck reaction upon seeing the old Captain when Thor shouldn’t be that surprised to see him after the events of Endgame, as the god of thunder didn’t seem privy to Steve’s time travel shenanigans. This is the kind of thing that I feel comes from fans spending so long thinking about something that they end up making a whole lot of nothing out to be much more than it is, and it seems like not everyone is convinced.

“I think people are going to pretzel themselves into some theories that simply aren’t true,” a redditor writes.

But there could be a Loki and Steve Rogers thread

Loki, having become a sort of caretaker for the multiverse’s timelines in his Disney+ show, is only briefly seen in the Doomsday trailer, but some fans are hypothesizing the antihero may have gone back in time to tell Steve, who went to the past to have a life with Peggy Carter, that his timeline is being threatened. Some are also speculating this might be among the additional scenes grafted on to the Endgame re-release, which is supposed to better connect the last Avengers movie with the next one, because god knows Marvel didn’t do that in anything it’s done in the seven years since.

My theory just got confirmed in the Avengers: Doomsday trailer.

Earlier I said Loki would visit Steve Rogers… and the trailer shows exactly that.

Loki shows up at Peggy’s house in his classic suit, just like we predicted.

Theory → Trailer confirmation.

This is why we… https://t.co/gWXAvOtdss pic.twitter.com/B5U6djtCOt

— Earth 616 (@MarvelExrth616) July 20, 2026

Doctor Doom’s power is from magic, not strength

One of the only glimpses we get of Doom in the trailer shows him blocking Thor’s Stormbreaker axe with what appears to be two fingers. However, if you look at his gauntlet, it seems to bear Latverian Sorcery Runes, implying that he is using some kind of magical energy to fight. As Marvel fans point out, this is something that makes him more formidable than Thanos.

In the comics Doom’s sorcery combines three distinct schools Latverian Runic Magic ancient spells permanently engraved into his armor creating a constant mystical barrier around his entire body.

The Dark Arts – learned from multiple sorcerers across different dimensions over decades of study. Doom is considered one of the most powerful sorcerers in Marvel history alongside Doctor Strange.

Soul Absorption – Doom previously trapped the souls of the Haazareth Three demons inside his armor to amplify his magical power beyond its natural limits

The runes on his gauntlet act as a mystic conductor – absorbing the full force of an Odinforce powered Thor strike and neutralizing it through enchantment. This is why Doom is categorically different from every MCU villain before him. Thanos needed six Infinity Stones. Doom has this level of power written permanently into his armor.

Avengers: Doomsday is coming to theaters on December 18.