Iron Man may have offered the ultimate sacrifice in Avengers: Endgame, but his seeming demise from the MCU doesn't stop fans from speculating about the character. After all, there are a lot of details that still haven't been filled in about Tony Stark, including information from the time before – and the time during – viewers knew him on their screens. Not to mention, given Iron Man's status as a fan favorite, the constant hope for more time with him in the future fuels fans in their theories.

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Here are 10 fan theories about Iron Man that we wish were true.

Iron Man is Peggy Carter's Godson

A popular theory about Iron Man is that Peggy Carter was an important figure in his life. Although Peggy and Howard never did "fondue," they were shown to be close friends in Captain America: The First Avenger and went on to found S.H.I.E.L.D. together after the war and Captain America's deep dive in the Atlantic.

Although the MCU never reveals anything about Tony and Peggy's relationship, fans enjoy this theory, because it neatly ties together the stories of Tony and Steve even more. Also, while the audience knows that Tony had Jarvis in his early life, they also know his relationship with his parents was stormy, even before their death. It would be nice to imagine that Tony had a strong, welcome influence like Peggy Carter in his life.

Iron Man Built Bucky Barnes A New Arm

Iron Man and Bucky fight in Captain America: Civil War

Although it is ultimately Shuri who makes a new arm for the one-time Winter Soldier, fans have often theorized that Tony might have created an arm as well. After all, there would be great narrative symmetry in this action, since Iron Man was the one to remove the arm in the first place.

In Spiderman: Homecoming, Happy mentions that Tony is working on a new shield for Steve, so an arm could have been tucked away somewhere as well. For Tony, building Bucky a new arm would be both an apology, for his actions in Civil War, and forgiveness, for Bucky killing his parents as the Winter Soldier, and would be a neat and powerful statement overall if it were true.

Iron Man Saved Peter Parker At The Stark Expo

In Iron Man 2, Tony Stark saves a small child in an Iron Man mask from death by drone and fans have long thought that this was none other than Spider-Man, Peter Parker. This theory makes a lot of sense, because Peter Parker is a nerdy kid, who loves tech, is excited by space, and overall has a big hero fanboy complex and so would have every reason to be visiting the expo.

Also, it doesn't hurt that he lives in Queens, the location of the Stark Expo. While this theory has actually been confirmed by Tom Holland and Kevin Feige off-screen, there has never been any actual on-screen reference to it. Going forward, it could be a nice story for Peter Parker to share with Morgan about her father as she reaches an age similar to Peter in the story.

Iron Man and Captain America are BFFS

It's sad for many fans that this theory is really only a theory, but alas, there is very little canonical evidence for a deep friendship between the two characters. While Tony tells Steve at the end of Civil War that he was his friend, the MCU doesn't do much work to show the audience this.

Fans have long craved a more fleshed-out version of many relationships, but none more so than between these two original Avengers, who are often portrayed as incredibly close in the comics. Although both Cap and Tony seem to have taken a seat on the benches, for now, it doesn't stop fans from wishing they could see more friendly interactions between the two.

Iron Man is Bisexual

Take it as part of the Cap friendship theory or not, for many fans this is one important theory. The notion that Iron Man is bisexual is strongly implied, or even flat out portrayed, in the comics, and would be an amazing feature in the MCU. After all, the audience has seen Tony Stark flirting with a lot of women, but also admiring many men... Commenting on Captain America's...assets in Endgame, anyone?

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It's no wonder fans love this theory, because for a character as popular, nuanced, and heroic as Iron Man to be used to shed light on such an underrepresented identity would be nothing short of powerful.

Iron Man Met Shuri

Many fans hoped that this meeting of the minds would take place in either Infinity War of Endgame, but it never seemed to come to pass... Or did it? In Infinity War, Tony's latest Iron Man suit uses the same kind of nanotechnology that Shuri's Black Panther suits use in Black Panther, and his new gauntlet design does look very reminiscent of Shuri's own blasters.

Shuri's actress, Letitia Wright, even hinted something was afoot before Infinity War.  Though this theory was never confirmed, fans hope the two geniuses got a chance to riff off one another and hope even more that, one day, the audience will be able to enjoy it.

Iron Man Can Wield Mjölnir

In Avengers: Age of Ultron, it seems like only Thor is capable of wielding his mighty hammer, but as the MCU has unfolded, more and more characters have revealed the same capability, creating speculation about who else might be able to use the powerful weapon. Tony Stark has always been surrounded by questions of worth, whether or not he was just a "big man in a suit of armor" or whether he was truly a hero when it counted.

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Throughout the movies, Tony has shown that he definitely has evolved and grown as a character and a hero, one who ultimately makes the sacrifice play. Fans believe that, surely, after the end of Endgame, if Marvel were to ever bring Tony Stark back into the picture, he too would be deemed worthy.

Iron Man Left A Will Addressing The Avengers

There are still a lot of unanswered questions regarding Tony and his relationships with the other heroes around him. The audience sees them all at his funeral, but the original Avengers, for the most part, do not get to say a direct goodbye to Tony Stark.

In Spider-Man: Far From Home, the notion of a will is introduced, and perhaps will recur. From Thor to Steve, to Bruce Banner, and others, having one last communication with Iron Man would create necessary closure between the Avengers and their fallen friend.

Iron Man Is Backed Up In AI

Although a static piece of communication would be nice, perhaps there is an even better option. Fans, calling specific attention to the projection of Tony Stark seen at the end of Endgame, have offered the theory that Tony Stark is backed up in the form of AI. Tony has long been obsessed with many forms of artificial intelligence, including J.A.R.V.I.S, F.R.I.D.A.Y, and most recently E.D.I.T.H.

With a young daughter and a distinct fondness for himself, it doesn't seem outlandish to imagine that Tony Stark would back himself up in the best way he knew how. This kind of set up has also been done in the comics before and could set up a future, much hoped for, Ironheart storyline.

Iron Man Is Alive

Of course, the ultimate fan theory about Iron Man is that, somehow, Tony Stark is still alive. Although he seemed very done for at the end of Endgame, with time travel, alternate dimensions, advanced technology, and more, there are a plethora of ways Tony could rejoin the MCU.

With so many characters still to interact with, so many theories still to explore, and so many fans cheering this on, it's clear that the audience wishes there was a way for Tony Stark to get one more shot at living.

NEXT: Tony Stark’s 10 Most Heartwarming Moments In The MCU