The end of Avengers: Infinity War was one of the most surprising moments of 2018. The heroes, in all their efforts, had failed to save the universe. Thanos, the villain, had achieved his ultimate goal of eliminating half of all life throughout the universe. As audiences watched the heroes they love fade away into dust, they realized that Marvel had just pulled the rug out from under them. This was not a victory in even the slightest sense. The Avengers had been defeated and everyone had paid the price. These last minutes of the film led to endless discussions about where the MCU would go after this and how the remaining heroes of Earth would be able to put things right. Then, the trailer for Avengers: Endgame was released and the conversations and theories started spreading like wildfire.

Where is Thanos? What happened to Hawkeye? How will Ant-Man play into things? Who will save Tony from being marooned in space? There were so many questions that people wanted to answer and the end of the previous film just made them want to find the solutions even more. Fan theories have been pouring out on every corner of the internet. People are postulating as to how the heroes are going to win the day and how the universe is going to move forward. Some of these theories are completely absurd and they don't hold water under even the slightest bit of scrutiny. However, some of these theories seem like they could become a reality. They use everything we know about the MCU to put forth ideas of how the story of Earth's Mightiest Heroes might come to an end. We'll have to wait until April to find out.

20 POSSIBLE: THE STORY WILL INVOLVE TIME TRAVEL

Right from the moment everyone witnessed the snap and the disappearance of half of all life in the universe at the end of Avengers: Infinity War, there was speculation as to how the remaining heroes would be able to save the entire universe and bring back everyone they care about.

One of the prevailing theories is that there will be an element of time travel to the story. Whether that involves utilizing the Time Stone or having Ant-Man somehow utilize a time vortex, fans are sure that all of the remaining Avengers will have to jump backward (and maybe even forward) in time to stop Thanos from winning.

19 ABSURD: PEPPER POTTS WILL SAVE TONY

Pepper Potts may end up playing a larger role in Avengers: Endgame. It might even be the thing that convinced Gwyneth Paltrow to keep playing the role. One fan theory has suggested that Pepper will be the one to save Tony from the depths of space, utilizing her own Stark suit and becoming the MCU version of Rescue.

This, however, is highly unlikely. It's not that we don't want to see Pepper in action or that we think she will be given the short end of the stick in the film. It's just that Tony is lightyears away from Earth, in a totally uncharted region of space. Pepper wouldn't be able to reach him without some kind of portal or teleportation device, which would be too much of a cheat.

18 POSSIBLE: CAPTAIN MARVEL WON'T SAVE TONY

There has also been a lot of speculation that the person who will rescue Tony from the depths of space and bring him back to Earth will be Captain Marvel herself, Carol Danvers. Captain Marvel is set to be introduced in her own film just a month before Avengers: Endgame and her inclusion in the story was already hinted at in Infinity War's post-credits scene.

However, Marvel has a way of subverting expectations. Just look at the ending of their last movie! It might just be too predictable or easy that Captain Marvel would fly in and find Tony, bringing him back to Earth with no conflict. Besides, Tony has gotten himself out of some intense situations before. Maybe he can do it again?

17 ABSURD: TONY WILL GATHER THE INFINITY STONES AND REVERSE THE SNAP

Infinity War spent a lot of its time following Thanos' journey to gather the Infinity Stones and complete his task. After he snapped his fingers and carried out his will, the gauntlet looked pretty banged up. There's no indication of where it is or what shape it is in at this point. Thanos definitely did not have it on his hand at the end of the film.

One theory that is floating around, but probably won't be taken seriously, is that Tony will gather the Infinity Stones himself and use the gauntlet to reverse the snap. The theory also states that this move will be the end of Tony, as it will just drain him completely. There are a lot of possible ways to conclude this massive story arc, but this definitely isn't going to be it.

16 POSSIBLE: ANT-MAN WILL BE THE ONE TO INTRODUCE REAL TIME TRAVEL

While we have already seen what Doctor Strange can do with time using the Time Stone, there is one hero who may just be the one to introduce longer-term time travel to the Avengers: Ant-Man. while he hasn't gotten a lot of shrift within the MCU, he may just be one of the most important parts of its biggest story yet.

After all, when Janet van Dyne tells Scott Lang not to get lost in a time vortex, it is a very clear and deliberate piece of dialogue. Why would she mention it unless it was going to be important later on? Not to mention the fact that Scott gets out of the Quantum Realm on his own, somehow. Maybe he discovers a way to control and utilize those vortexes?

15 ABSURD: ANT-MAN ISN'T ACTUALLY AT THE FRONT DOOR

One of the best parts of the Avengers: Endgame trailer was the moment right at the end, where Scott Lang is practically knocking on the front door of the Avengers compound. He asks if he can be buzzed in and it seems like this is a hint that he is going to be playing a fairly big role in how the story plays out.

However, some fan theories are suggesting that Scott is not actually at the front door at that moment. They speculate that due to a time vortex, he may actually be stuck in the past and what Natasha and Steve are watching is an archived video. However, this seems like a needless complication to the plot and it's more likely that Scott really is just at the front door.

14 POSSIBLE: LADY DEATH WILL MAKE HER FILM DEBUT

In Marvel comics, Thanos wanted to eliminate half of all life in the universe for one reason only: to court Lady Death. He has always had romantic feelings for her and has tried through almost his entire existence to win her approval. Even the MCU has hinted at this, with the relationship being hinted at in the post-credits scene of The Avengers.

Some fan theories have now speculated that Lady Death may, in fact, make her appearance in the MCU in Avengers: Endgame. After all, there has to be more to Thanos' motivation than simply wanting there to be enough resources for everyone. Why would he care whether the people of Earth or any other planet had enough resources? There has to be something more and this may just be it.

13 ABSURD: THANOS AND THE AVENGERS TEAM UP

Thanos is definitely the greatest foe the Avengers have faced (so far). His relentless search for the Infinity Stones put him entirely at odds with the World's Mightiest Heroes, who knew that if he was able to get his hands on them, then he would definitely carry out his nefarious plan.

So why in the world is there a fan theory out there that says the Avengers and Thanos will team up to fight a greater threat? It just doesn't seem like a likely occurrence. Could Thanos regret his decision by the end of the film? Possibly. That definitely does not mean that he and the Avengers will work together in any way.

12 POSSIBLE: STRANGE KNEW EXACTLY WHEN TO HAND OVER THE TIME STONE

During the battle on Titan, Tony Stark was about to meet his end at the hands of Thanos. Luckily for him (although unluckily for everyone else, maybe), Doctor Strange was willing to give up the Time Stone to spare Tony's life. We know that Strange had already looked through every possible timeline and saw only one where the heroes succeeded, so this must have been part of the plan.

However, there is now more to the theory that includes the post-credits scene of Ant-Man and the Wasp. The new fan theory puts forth the idea that Strange knew that there was an exact moment he had to hand over the time stone in order to ensure that Scott Lang would be in the Quantum Realm and would be unaffected by the snap. This might just be exactly why Strange gave up the Stone and told Tony it was the only way.

11 ABSURD: HAWKEYE LOST HIS FAMILY BEFORE THE SNAP

Hawkeye's family was introduced in Avengers: Age of Ultron, and aside from being a moment that showed how some of these heroes have a life outside of their work, it might have just been an important story moment. The most recent Hawkeye sighting saw him taking a very different approach to his work in the Avengers: Endgame trailer.

Some fan theories have said that Hawkeye's family probably faded away after the snap, leaving him alone. However, another fan theory suggests that Clint lost his family before the snap even happened, in some other tragic fashion. This seems highly unlikely, though. Why would Marvel be so heartless as to get rid of Clint's family with no chance of them coming back? It also seems weird from a story standpoint, as it would make more sense to the overall plot if they had been snapped away.

10 POSSIBLE: THANOS SNAPPED HIMSELF

Audiences had to watch as a lot of their favorite heroes faded away into dust, leaving the other Avengers entirely speechless. It was a sobering moment and a reminder that the MCU still has ways of surprising people. How could they ever top that moment with anything else in Avengers: Endgame?

One fan theory has suggested that among the beings who were snapped away from existence was actually Thanos himself. After all, the next time he is seen, there is no indication as to where he ended up and yet somehow, it just seemed that there was a perfect spot for him. His idyllic and peaceful final moment may have been an indication that he faded away like everyone else.

9 ABSURD: NEBULA WILL BE THE ONE TO DEFEAT THANOS

Nebula has always been the lesser of Thanos' daughters, at least in the Mad Titan's eyes. She constantly lost to her sister Gamora, leading Thanos to continually augment her with technology. She may have had a grudge against Gamora, but she never would have actually put an end to her, unlike their father.

A new fan theory states that it might just be Nebula who deals the final blow to Thanos and ends everything. However, this seems like it would really be bad for the arcs of all the other heroes, particularly Cap and Iron Man, who will most likely see their roles completed in the final film. Nebula might get her time to shine, but she won't be the one to end things.

8 POSSIBLE: PEPPER POTTS JOINS THE FIGHT AGAINST THANOS

We already said that it is unlikely that Pepper will be the one to save Tony from space. After all, she would have to travel millions of miles in order to just get close to where he is and then she would still have to actually locate him. However, this doesn't mean that Pepper won't be in the final battle for the universe.

Pepper may very well finally get the chance to be a hero if she suits up and becomes Rescue, her adopted persona when she wears her own specially-designed Stark suit. As we mentioned before, this might have been the thing that kept Gwyneth Paltrow in the role, since it would certainly be a great final moment for the character.

7 ABSURD: HAWKEYE IS A SKRULL

So apparently Hawkeye has really gone through some stuff by the time he shows up again in Avengers: Endgame. As mentioned above, there is the distinct possibility that his family was either snapped away or may have been taken from him in some other way (although that is less likely).

Hawkeye has acted differently in the comics before, taking on the persona of Ronin when things got really dark after the events of Civil War. So it's a little strange that at least one fan theory has suggested this Clint Barton is actually a Skrull, which is why he is acting so strange. We're just going to go ahead and say "no" to this one, entirely.

6 POSSIBLE: THANOS WILL REDEEM HIMSELF

One of the most surprising aspects of Avengers: Infinity War was how it gave the film's main character arc to its villain. Thanos basically went through all the stages that a protagonist goes through on their way to their ultimate goal. However, instead of doing something good at the end, Thanos eliminated half of all life in the universe.

Does that mean that Thanos can't eventually see the error of his ways? Maybe not! Some fan theories posit that Thanos might actually be able to redeem himself in Endgame. After all, he must be feeling some remorse about trading Gamora for the Soul Stone, and the scene in the Soul Stone realm when he confronts Gamora as a child has to mean something going forward.

5 ABSURD: ANT-MAN WILL TAKE THE AVENGERS INTO THE QUANTUM REALM

We all know by now that Scott Lang seems fairly comfortable traveling into the Quantum Realm. It's practically a walk in the park for him at this point. However, the last time we saw him (before his revel in the Endgame trailer), he was stuck there, with no one to pull him back out.

Now, there is one fan theory circulating that Ant-Man will have to take the rest of the Avengers into the Quantum Realm with him because that will be the only way to defeat Thanos. Unfortunately, this is pretty unlikely. After all, Ant-Man has a hard enough time getting out of there on his own. How is he going to bring that many people in and out with him in one piece?

4 POSSIBLE: AGE OF ULTRON PREDICTED THE END OF STEVE AND TONY

Almost as soon as the Avengers: Endgame trailer premiered, people were throwing this idea around. It harkened all the way back to the second chapter in the Avengers saga. The theory puts a particular focus on a conversation that Steve and Tony have in the final third of the film.

While observing the nation of Sokovia flying into the air, Tony expresses his doubt that the team who defeated an alien invasion in New York can handle it. When Steve says they will do it together, Tony replies, "we'll lose," to which Steve replies, "we'll do that together, too." Could this possibly be hinting at the fact that Tony and Steve will finally fully reconcile and give both of their lives to save the world? Stranger things have happened in the MCU.

3 ABSURD: THOR BUILDS AN ARMY IN ALFHEIM

Thor will most definitely be feeling the weight of defeat the hardest out of all of the remaining Avengers. After all, he was close to stopping Thanos, but one small mistake basically allowed him to complete his mission of erasing half of all life in the universe. That means that Thor may take it upon himself to do something about Thanos.

One fan theory suggests that Thor will visit the final realm known as Alfheim and rally together an army there to help win the day. However, this seems like it might be too far out of left field. Besides, if Alfheim is part of the universe, wouldn't half of their people also have been snapped away? This just doesn't seem like it will be the right solution.

2 POSSIBLE: CAPTAIN AMERICA WILL HAVE HIS HAPPY ENDING

There is a very intentional scene inserted into the Avengers: Endgame trailer and it is that of a compass with a photo of Peggy Carter inside. The compass is pointed squarely at her image and there is only one person in the world to whom this would hold any significance: Captain America.

Fan theories have, of course, suggested that Cap will meet his end in the finale of Endgame, but some of them go even further, suggesting that, like the Soul Stone sequence from the previous film, Steve will be reunited with Peggy and that they will finally have that dance that they waited decades to have.

1 ABSURD: A NEW UNIVERSE WITH THE SNAPPED HEROES

There is a prevailing fan theory floating around right now that the snap did not actually end half of all life in the universe. That is to say, what we were witnessing as we watched all of our favorite heroes fade away was not, in fact, the end of them, but rather a movement of these characters from one universe to another.

This theory posits that all of the people who got snapped will now exist in an alternate universe, where the remaining half of people who got to live have never existed. This theory is patently absurd because there is no way Marvel would ever be able to continue telling stories without acknowledging the past. Creating a new universe where there was never an Iron Man or a Captain America just wouldn't work.