9 Spoiler-Filled Questions and Theories We Have After Watching 'Avengers: Endgame'

Okay, you've been doubly warned, ready to dive into some major "Avengers: Endgame" spoilers?

Marvel did the unthinkable with this movie, weaving together characters and superheroes from 21 movies spanning over 10 years, ending an era of the MCU while ushering in a brand new one at the very same time. While the OG lineup suffered a few heartbreaking casualties -- and we'll get to those in a minute -- the movie also introduced bold new ideas teasing some exciting changes to come.

The MCU shows no signs of slowing down, with "Spider-Man: Far From Home" swinging into theaters and officially ending Phase 3 in less than three months. What's next is anyone's guess, especially taking the "Endgame" ending into consideration.

Obviously, anytime there's time travel involved, there are going to be a few loose ends. The main plot involved those who survived the Snap traveling back in time via the Quantum Realm to retrieve each of the Infinity Stones at different points and locations in MCU history. Hulk (Mark Ruffalo) then used the Infinity Gauntlet to reverse the deaths of millions, every superhero ever returned to fight Thanos and his army, before Tony Stark (Robert Downey Jr.) used the stones himself to dust all the bad guys.

Along the way, heroes were lost, some switched spots with their alternate selves and others made a few very surprising choices. Though we have a feeling Marvel will reveal some major announcements coming at either Comic-Con or Disney's own D23 this summer, for now we're left to speculate. Here are a few lingering questions and theories we're left pondering until then.

We'll address the more depressing outcomes in a second, but let's start with the happy ending: Captain America (Chris Evans) reuniting with Peggy Carter (Hayley Atwell) for that long-awaited dance.

After Thanos' snap was reversed, Cap happily volunteered to travel back in time (again) to return all the Infinity Stones to where they were retrieved, keeping the timeline intact. But instead of returning to the present after, he stayed in the past and lived a happy life with Peg. He then made it a point to shuffle back to the jump spot decades later as an old man, to let everyone know his decision and to pass his shield down to Falcon.

It appears we're supposed to believe old man Cap was always living in the world of the MCU, as young, unfrozen Cap did everything we saw him do in the previous movies. That's right, two Steves. For this to be true and to presumably keep the timeline intact, he and Peggy must have also somehow kept his identity a secret all these years, while he also chose not to reveal anything about the future to anyone ... even if it involved Hydra infiltrating S.H.I.E.L.D. or the torture of his BFF, Bucky.

If there's anyone who could shoulder that burden, it's America's best Boy Scout, especially if he's equipped with the knowledge the other him will help every step of the way.

Alright, onto the sad stuff. Tony Stark sacrificed himself to snap his Iron Infinity Gauntlet, leaving Pepper Potts (Gwyneth Paltrow) a widow and their daughter Morgan -- "I love you 3000" -- without a father. The world at large also lost one of the greatest film superheroes ever, one whose shoes will be hard to fill.

But ... will someone?

While we feel good knowing Shuri (Letitia Wright) is in this world to step into the role of brilliant scientist and tech master, we're curious if anyone will ever suit up in that iron armor. Fans have wanted Shuri to take it on and Pepper could always go full Rescue, but neither of those seem likely. First of all, Black Panther's sis seems to be doing just fine on her own ... and Gwyneth Paltrow recently said she's "a bit old to be in a suit and all that at this point."

A surprising face from Tony's funeral could also be an option, as a now-teenage Ty Simpkins popped up to reprise his role as Harley from "Iron Man 3." The kid who helped Tony at his worst could make for an interesting update and would also help bring down the median age of the Avengers again.

Then there's Ironheart, a young black engineering whiz from the comics who creates her own armor inspired by Iron Man's design. Adding a much younger female character to the mix could be a great route to go too, giving Spider-Man someone his own age to play off of as well.

The friendship between Natasha "Black Widow" Romanoff (Scarlett Johansson) and Clint "Hawkeye" Barton (Jeremy Renner) is one of the strongest in the MCU, a bond that was put to the ultimate test in "Endgame." They were the two sent back in time to retrieve the Soul Stone, a stone which requires the sacrifice of a loved one. The two fought to the very end over who would sacrifice themselves and Widow "won," giving Natasha a hero's death.

But, here's the thing, there's a "Black Widow" movie coming.

While Marvel hasn't ever officially commented on the movie -- other than Kevin Feige saying it won't have an R-rating -- it's in development, has a director in Cate Shortland and includes ScarJo and additional cast members David Harbour, Rachel Weisz, Florence Plugh and O-T Fagbenle.

The movie was rumored to be a prequel, something which now seems pretty much confirmed -- since she's dead -- and will likely fill one of Marvel's open slots for 2020.

Asgardians of the Galaxy, anyone? Thor's (Chris Hemsworth) journey in "Endgame" was kind of a frustrating one, as it found him drinking his life (and abs) away in guilt for not stopping the snap. After traveling back in time, he got a pep talk from his mom, who told him to find his true purpose in life.

That purpose, it seems, is not to be the ruler of his people, but instead join the Guardians of the Galaxy and leave Valkyrie (Tessa Thompson) in charge of New Asgard. That choice leads to some head-butting with Star-Lord (Chris Pratt) over who should be the true leader of the group.

Following the success of "Ragnarok," which really celebrated Hemsworth's until-then under-appreciated comedic chops, we can totally see him fitting right in with this crew if standalone "Thor" movies aren't going to be a thing anymore. But if there aren't any "Thor" movies, where does Valkyrie fit in? Because we need more of her, stat.

Speaking of the Guardians, we have a feeling the search for Gamora (Zoe Saldana) will be a major plot point in "Volume 3" when James Gunn gets behind the camera again for that one.

While the OG Gamora really was killed by Thanos and will remain dead, the past version of her jumped to the present day and bailed on her Mad Titan father just in the nick of time ... right? While we don't know for sure what happened to her, we're pretty sure she didn't get dusted with the rest of Thanos' army after Tony snapped his fingers.

Of course, this new version didn't seem all that impressed with Peter Quill and, if he finds her, he'll have to grow on her all over again. Even if he can't, let's face it, we really just want to see Nebula (Karen Gillan) and her sister together again.

Before the movie's release, Disney confirmed its upcoming Disney+ streaming service will have a number of Marvel shows coming to it. First up is "The Falcon & the Winter Soldier."

Of course, thanks to the events of "Endgame," The Falcon (Anthony Mackie) is actually Captain America now ... or at least is on his way to becoming him. And since the show can't really be a prequel -- Bucky (Sebastian Stan) was either in WWII, brainwashed, in Wakanda or dust since he's been around -- it will have to at least acknowledge Falcon's path to Cap-dom or change its title altogether.

Or it could just be set in an alternate universe, who knows!

Another show shrouded in mystery is the ridiculously-title "WandaVision," about, you guessed it, Wanda and Vision. There are no details about this show either, except the confirmation that both Elizabeth Olsen and Paul Bettany will reprise their roles. Since Vision is still dead after Thanos ripped the Power stone from his forehead, will this one be a prequel series set somewhere between "Age of Ultron" and "Infinity War"? Or can Shuri and Helen Cho somehow make a new Vision using whatever data the former mapped from his brain?

So. Many. Questions. And we haven't even gotten to the biggest one yet. Which brings us to ...

Like Gamora and Vision, Loki's "Infinity War" death also seems to be permanent. But since he's a favorite character of the MCU and a Disney+ show is coming about Asgard's most lovable trickster, Past Loki found an escape route.

When the Avengers traveled back to the Battle of New York, they botched their mission entirely and Loki ended up disappearing with the Tesseract and the Space Stone located inside it. How this doesn't totally ruin the timeline is beyond us -- the time travel logic in this movie is all over the place -- but Loki's on the loose.

Either a future movie or his standalone show will have to fill in the blanks on where he went, but we're just glad Tom Hiddleston's still around.

When Peter Parker (Tom Holland) returns to school in "Spider-Man: Far From Home," how many of his old classmates will still be there? We know there was a five year time jump between when half the population vanished and when they returned and five years is a lot for a teenager.

Since Ned (Jacob Batalon) was at school when Peter got back at the end, he must have gone bye bye as well ... or he became so overcome with grief he stayed back five years. Zendaya's MJ, Angourie Rice's Betty and Tony Revolori's Flash also likely dusted since they're in the "Far From Home" trailer on a school trip with Peter.

Nowhere to be found, however, is Laura Harrier's Liz, daughter of Vulture.

Also worth noting: Fans pointed out some flirting between Happy Hogan (Jon Favreau) and Aunt May (Marisa Tomei) in the trailer -- could they have started up a relationship in the five years since Peter disappeared?!

Last, but certainly not least, we need to talk about that one shot of "Endgame." You know the one: Captain Marvel (Brie Larson) getting backup from nearly every female character in the MCU.

We just got our first female-fronted Marvel film earlier this year and now, we want more. So much more. Like, "Avengers" movie of all the women more. It'll take an awkward line of exposition to explain away the guys, but seeing them all share the screen again -- with the help of Maria Hill (Cobie Smulders) and randomly MIA Nakia (Lupita Nyong'o) -- would be more than welcome.

Also, can the Avengers figure out a better way to get in contact with Captain Marvel? Just a general suggestion in case another all-powerful madman makes a trip to Earth.

"Avengers: Endgame" is in theaters now.