Avengers: Endgame may be the only Marvel movie you need to rewatch before Doomsday, and here's why

Remember when Marvel released an Avengers movie with "end" in the title, and we all thought it might be the last Avengers movie ever... or at least for another 10 years? Well, it was the last one for six years, and it was a much-needed pause. Since the 2019 release of Avengers: Endgame, the Marvel Cinematic Universe has stretched and grown and changed quite a bit.

Endgame brought everyone back from the Blip, closed the book on two of our favorite heroes, reset Earth-616, and killed off the MCU's biggest supervillain thus far. After the Avengers disbanded, Tom Holland's Spider-Man became a fully fleshed-out hero; WandaVision ushered in the first new era of Marvel TV since the pre-Disney Netflix run; we met Shang-Chi and Yelena Belova; Loki taught us about the infinite possibilities scattered throughout time and space, and we ran headfirst into the multiverse.

In a nutshell, we have a lot to thank Endgame for. And we can't roll into theaters in December to watch Robert Downey Jr. do that scary new accent in a green cloak until we spend some time revisiting the biggest Marvel movie of all time.

Remember how Thanos was almost presented as a protagonist in Infinity War (even though he strangled Loki to death with his bare hands)? Yeah, Endgame takes all of that back and gives us a decapitation scene within the first act. Of course, this doesn't kill him kill him. Instead, we're introduced to a slew of alternate realities, jump back and forth between different decades, and ultimately see that big purple freak hijack a time machine (made by Tony, Rocket, and Bruce Banner, mind you) and return to the present to kill everything in sight.

It was our first real instance of, "Wait, can they do that?" Well, maybe our first real instance of unending possibilities was when Bucky Barnes somehow survived that fall in Captain America: The First Avenger, only to come back as the villain in The Winter Soldier. But Endgame showed us that everything exists all at once, and that there are variants upon variants of every hero we love (something that doesn't truly hit home until Doctor Strange in the Multiverse of Madness)... and therefore, anything can happen in the Marvel Cinematic Universe.

That includes putting an end to Robert Downey Jr.'s decade-plus run as Tony Stark aka Iron Man. And just as Peter Parker was blipped away in Tony's arms, Peter is the last person to speak to Tony in his final moments, just before his eyes close.

The end of the beginning

Though Captain America might be the first Avenger, Iron Man was the glue that held the supergroup together. As it turns out, you need a billionaire playboy philanthropist with access to tech beyond our wildest dreams in order to save the world one or a dozen times. It's also in the way Downey portrayed Tony Stark, no matter who was directing or writing – the combination of heart, snark, and well-meaning arrogance was consistent throughout every appearance (while some characters, like Chris Hemsworth's Thor, for example, waxed and waned throughout).

Tony Stark, long-believed by many to be a heartless bastard, ultimately sacrificed himself to save humanity as we know it. It's the absence of Iron Man on Earth-616 that made room for a new slew of heroes to come through, and it allowed Peter Parker to come into his own (or made him grow up a bit too fast, depending on how you're looking at it).

Is it going to be weird seeing Downey leave the heroism behind in order to portray the greatest threat to the MCU since Thanos in Avengers: Doomsday? Probably. But it's sort of beautiful: his last performance as a hero saw him make a selfless and fatal sacrifice, only for him to return as a supervillain who only cares about himself... and will most likely remain unkillable beyond the events of Avengers: Secret Wars. It only makes sense to go back and watch Endgame before watching Doomsday, if not for the stark (pun intended) contrast in characters.

Can I get an encore?

All that said... do you need to head on over to the theater to watch Avengers: Endgame Encore? Yes and no, and I'll attempt to explain why in the least spoiler-y way possible.

While Infinity War and Endgame very loosely adapt Jim Starlin's 1990 comic Thanos Quest and the 1991 comic The Infinity Gauntlet, Doomsday feels like a pretty faithful adaptation of Jonathan Hickman's Avengers run... which then takes us all the way into Avengers: Secret Wars. It hasn't been confirmed that Marvel is using Hickman's Avengers (which includes the 2015 Secret Wars event) as a road map for the next phase of the MCU, but the four post-credits scenes included in Avengers: Endgame Encore say otherwise. In my opinion, they all but confirm it.

Though the original movie itself remains unchanged, the four stingers added to the Encore version of Endgame attempt to bridge the gap between Endgame and Doomsday. The scenes show us what happened to certain heroes (particularly one whose fate remains unknown after the events of Spider-Man: Brand New Day, and has not been confirmed to appear in Doomsday), briefly explain how another managed to defy the laws of time, and foreshadow what will happen to our heroes on their respective planets in Doomsday.

You don't need all of this new info in order to see or enjoy Doomsday, but it does add an extra oomph to Endgame for all of us who felt a little sad and empty after initially watching it six or so years ago. You can also watch it in InfinityVision, which is basically Marvel's version of IMAX.

Are you ready to cry all over again, dear reader? Of course you are. There are several movies that Disney Plus lists as required viewing as we prepare for Avengers: Doomsday, but if you had to watch one, just one... it's Avengers: Endgame. Now go tell someone that you love them 3000.

Avengers: Endgame is available to stream now on Disney Plus, ahead of the release of Avengers: Doomsday on December 18. Avengers: Endgame Encore is in theaters now.

Look ahead with our list of upcoming Marvel movies and check out how to watch the Marvel movies in order ahead of your next re-watch. See you next week as we revisit Avengers: Infinity War.