'Avengers: Endgame' Easter Egg Reveals How Tony Really Cracked Time Travel

With the digital and Blu-ray release of Avengers: Endgame, Marvel fans have been rewatching the movie and uncovering tons of new details, from hidden references to MCU history to secret character Easter eggs. But one new, overlooked detail may top them all by offering a peek inside the brain of Tony Stark.

Not even Professor Hulk could figure out time travel in Avengers: Endgame. It took Iron Man to solve the complex math, but even then, it turns out he needed a little inspiration from an unlikely source. As one fan recently pointed out, Tony might have never cracked the equation if it wasn’t for a series of coincidences that you probably missed while watching Endgame in theaters.

As you probably remember, Tony initially refuses to help the other Avengers in their efforts to travel back in time and undo Thanos’ Snap. He doesn’t change his mind until later that night when he’s doing the dishes and accidentally sprays water all over a framed photo of him posing with Peter Parker. Presumably, the memory of his dusted mentee is what motivates Tony to figure out time travel. But maybe there’s more to it than that.

However, as redditor u/discr33t_enough notes, it’s a little more complicated than that. A closer look at the photo in question reveals that the diploma Tony and Peter are holding is upside down, which seems insignificant until you remember the next thing Tony Stark says in Endgame while speaking to his computer:

I’ve got a mild inspiration. So I’d like to run one last sim. This time, in the shape of a mobius strip. Inverted, please.

Get it? Not even Tony Stark could have solved time travel if it wasn’t for the upside down diploma. That’s what gave him the idea to flip the mobius strip (whatever that means).

Of course, this raises another important question: Could Tony have figured out time travel without this little bit of inspiration? We’d like to think the answer is yes, but there’s no way to know for sure (aside from maybe asking the Russo Brothers).

Then again, it may not matter. Because as much as the whole inverted diploma might have helped, Tony still wouldn’t have even tried to solve quantum realm time travel if it wasn’t for his close bond with Peter Parker. It took a mix of emotions and nostalgia to get the job done. Either one on its own simply wouldn’t have been enough.

Avengers: Endgame is available now on digital platforms and Blu-ray.