Detailed MCU Fan Theories That Actually Make A Lot Of Sense

Voting Rules

Vote up the most interesting (and believable) fan theories about the Marvel Cinematic Universe.

The MCU has been going strong for well over a decade now, and with the dozens of movies and television shows Marvel has thrown into the world, there are fans of all sorts. Fans of the MCU have had some pretty interesting ideas over the years. When those folks find themselves online discussing their favorite aspects of Iron Man, Spider-Man, other heroes, villains, and events in the MCU, you're going to end up with some pretty interesting fan theories.

Every so often, fans will take their theory to the FanTheories subreddit to share their thoughts and ideas behind the characters and events that make the MCU such an incredible franchise. Some fan theories actually make a lot of sense, and the best of them have been compiled here. Take a look at them down below, and if you find a fan theory that makes you think twice about something related to the MCU, be sure to give it an upvote before you go!


  • 1
    1,531 VOTES

    There's A Reason Steve Could Stop Thanos's Fist In 'Infinity War'

    From Redditor u/XanPerkyCheck:

    I'm referring to at 0:33 in this video: https://www.youtube.com/watch?v=6pd0Pk5av2s

    Thanos moves his glove hand towards Rogers, and Rogers stops it with both hands. Thanos strains a bit more but is unable to move his hand forward or close his grip, so he just knocks Rogers out with his non-glove hand instead.

    If you look at his facial expression, he looks shocked at 0:34 upon the initial block, then at 0:38 onwards he looks really perplexed with his eyes squinting and all like he's thinking "how is this guy able to do this"? But what is 'this' that Rogers is doing?

    I don't believe it's physically blocking Thanos' hand. Thanos beat up Hulk, and Rogers is definitely not stronger than Hulk, not to mention Thanos knocks out Rogers seconds later, while Rogers' uppercut punch at 0:30 did nothing to Thanos.

    The glove works by responding to the will of the user, and at that moment, both of them were in physical contact with the glove. So Rogers was kind of "out-willing" Thanos, and while none of the infinity stones were actively being used, they were implicitly responding to both Thanos' and Rogers' wills respectively, with Rogers' influence being greater. And that's how he was able to resist Thanos.

    1,531 votes
  • 2
    1,029 VOTES

    Doctor Strange Was Wrong About Defeating Thanos

    From a now-deleted Redditor:

    This is my own spin on u/Arc_the_lad 's theory on Dr. Strange. I personally don't think of him as a bad guy, so here's my theory:

    Right before she dies, the Ancient One talks to Doctor Strange in her astral form and she mentions that she can't see past the point of her death.

    “I've spent so many years peering through time, looking at this exact moment. But I can't see past it. I've prevented countless terrible futures and after each one there's always another, and they all lead here but never further.”

    So even with the Time stone in her possession, the Ancient One could not see past her own death. In the MCU continuity, there is no evidence to suggest that Doctor Strange has surpassed her skills as a wizard or as a user of the Time Stone.

    This clearly establishes the fact that when Strange was seeing all those possible future outcomes on Titan, he counted every possibility where he dies (not snapped, but literally dies) as a failure.

    This basically means that out of all the possible outcomes, Doctor Strange survived in 14,000,605, and out of those, there was only one in which the Avengers won.

    This implies that there may have been hundreds of outcomes for the final battle, in which our heroes emerge victorious without Stark's sacrifice, but Strange couldn't envision those outcomes because he had been a casualty along the way.

    So, instead of Strange being a diabolical evil mastermind, maybe he wasn't able to find a possibility where the Avengers won while he was dead. This possibility was the only one where he was alive after the end of Endgame. Maybe there was a reality where he died, but Tony survived?

    1,029 votes
  • 3
    705 VOTES

    Tony Stark's Iron Man Suits Become Weaker Over Time

    From Redditor u/meme_abstinent:

    I see a lot of comments on content having to do with Iron-Man's suits, pointing out how borderline invulnerable they were at first, and eventually got weak. Point to Iron-Man one where he walks off a tank blast to Civil War where Cap does ample amounts of damage with his bare hands and shield.

    My logic behind how this is possible is simple.

    Stark trades in durability for speed and focuses on making his suits more capable throughout the MCU.

    Take Iron-Man one. The Iron-Man suit was a suit of armor initially and had very limited capabilities combat-wise.

    Iron-Man 2, we see Tony take damage easier but has lasers, missiles, machine guns, etc.

    Iron-Man 3 and almost most noticeably, his suits take the most damage (breaks by a van slamming into it) but now his suits can come to him, fight on their own I.E autopilot, and are made, sometimes, with specific purposes.

    This method begins to pay off, as Stark begins playing with nano-tech in Civil War. Ultimately, his suits reach maximum durability through this experimentation, as the Iron-Man suit is capable of withstanding concentrated energy blasts from the Power Stone in Infinity War.

    I also feel Stark purposefully ditches so much armor on his suit because he knows he's better with his suits. Tony knows that with more and more use with his suits, he's becoming better at flying and dodging and fighting. This is illustrated perfectly in Civil War and Infinity War as he dodges, blocks, and is now doing complex flips and spins mid-flight.

    705 votes
  • 4
    685 VOTES

    Peter Quill's Upbringing Influences How He Hears Aliens In The MCU

    From Redditor u/freelanceastronaut:

    Why everyone in Guardians of the Galaxy sounds like they're in a PG-13 film

    The reason that the language in both Guardians of the Galaxy movies is frequently juvenile and all profanity seems limited to the constraints of a PG-13 film is because we're usually hearing it as Starlord hears it through his universal translator (mentioned onscreen in the first movie's mugshot scene).

    Starlord was taken from Earth when he was eight. He probably stopped actually learning English shortly after, since it's unlikely that he had anyone else to actually speak it with. As such, his language (and all language he hears) is going to seem juvenile. Additionally, any profanity he knows probably came from movies and TV shows he saw before he was kidnapped.

    685 votes
  • 5
    577 VOTES

    There's A Reason Odin Attempted To Conquer The Nine Realms

    From Redditor u/bubonis:

    The fake Infinity Gauntlet at Asgard, Hela's and Odin's early lives, and Thanos ordering a Gauntlet from Nidavellir.

    While I admit there's virtually no evidence to support most if not all of this, I think this theory fits in well with the canon timeline and information available.

    Years and years ago, Odin learned about the Infinity Stones through his father, Bor, who was responsible for taking the Reality Stone from the Dark Elves. After his death and Odin's subsequent rise to power, he (with Hela at his side) began conquering all the realms in order to locate and claim the Stones. Odin found the Space Stone first and this allowed Odin and his armies to travel between realms and conquer them very quickly. the Bifrost is essentially an Asgardian reproduction of the power of the Space Stone (EDIT: Never mind that bit.) During this, he commissioned Nidavellir to create a device that would allow him to control all the Stones at will: the Infinity Gauntlet. They created the mold for it and made one casting as a test fit for Odin, complete with fake Stones to give Odin an idea of the grandeur of the finished Gauntlet.

    However, at about this time he discovered the whereabouts of the Soul Stone and what was required of him to get it: He'd have to sacrifice that which he loved the most, which was Hela. He found he couldn't do it and at that moment Odin stopped being a conquerer and started being a king. Hela didn't understand this change of heart; she knew what the Infinity Stones were because Odin specifically told her that's why they were conquering all the realms, and Hela believed in that power more than anything else. So she and Odin fought; Odin won and that's when he imprisoned her in Hell. Odin put the fake Gauntlet in his treasure room as a reminder of both what he'd done and what he'd lost, and swore that he would protect all that he had conquered. Thus he became Odin Allfather, Protector of the Nine Realms. Nidavellir decommissioned the Gauntlet mold and Odin hid the Space Stone on Midgard. Odin almost definitely knew where the Reality Stone was because Odin's father had it at one time. If this theory is true then he definitely knew where the Soul Stone was, he might have known where the Power Stone was, he probably didn't know the Time Stone was also already on Midgard (otherwise he likely wouldn't have risked two Infinity Stones in the same place), and he almost definitely didn't know where the Mind Stone was.

    When Thanos arrived on the scene and went to Nidavellir to have them forge a control for the Stones, they used their previous knowledge from Odin's Gauntlet to make one for Thanos.

    If this theory were true then it explains how and why Odin was previously a conquerer and why he changed; why there's a fake Infinity Gauntlet in Odin's treasure room; how Hela knows it's fake; how Hela knows what the Tesseract is ("That's not bad," she says while giving a small pause in front of it); why Odin changed from conqueror to king; why Odin and Hela fought; and why Thanos' Gauntlet is basically the same as the fake Gauntlet at Asgard.

    EDIT/BONUS 1: I thought of something else. Odin may have used the Space Stone to banish Hela to Hell, which may be considered unnatural since Hell isn't supposed to be for living beings. That being the case, Odin "tampered with natural law" and the bill came due by way of the Ragnarok prophecy. The destruction of Asgard may have been the universe's way of balancing itself out.

    EDIT/BONUS 2: And another thing... Odin himself said that Thor was stronger than him. You could argue that "young Thor" is stronger than "old man Odin" and you'd probably be right, but what if Odin meant that Thor is always stronger than Odin? That Odin in his prime couldn't have beaten Thor? If that's true then the question becomes: If Thor is always stronger than Odin, and Thor couldn't defeat Hela, then how did weaker Odin defeat Hela? A possible answer is that Odin held the Space Stone. Odin's power, amplified by the abilities and power of the Space Stone, may have been enough to tip the fight Odin's way.

    577 votes
  • 6
    413 VOTES

    Peter Parker's Comments About "Really Old Movies" Comes From Uncle Ben

    From Redditor u/ScoobyQuinn23:

    I have a theory about the MCU Uncle Ben. So far obviously we haven't seen him we've only gotten subtle remarks about him but I think there's a way Peter always carries Ben with him, through his movie references.

    My theory is that Uncle Ben was a film nut and he loved sharing his favorite movies with Peter... All the references Peter has used so far are all from "really old movies" that would've come out when Uncle Ben was around 20 based on Aunt May's age. 

    Sure Peter could've seen all those movies on his own, especially Star Wars but I've met kids from his generation that have never seen Wizard of Oz or Back to the Future let alone Aliens or Ferris Bueller. So all these movies made an impact on a young Uncle Ben (some of which he may have even seen in the theater with Peter's father) so he showed them to Peter and Peter loved most of them, but not all of them judging by his remarks on Footloose

    I think this is also why Homecoming begins with "A Film by Peter Parker" he filmed it knowing he couldn't show it to anyone so I think he was making it for Ben. Peter found himself right in the middle of the kind of movie Uncle Ben would've loved so he just had to film it. I can't prove this theory and it really doesn't change anything major. It's just something I like to believe because to me it brings more depth to the new Spider-Man and adds an emotional element to some of his quips.

    413 votes