The title of endgame makes a lot of sense. It refers to a scenario in chess when very few pieces are left to play with on the board. Which makes sense when you consider that Thanos snapped the world and cleared a lot of heroes. Endgame is also used in chess to refer to a kind of play where a checkmate scenario has been enacted against the opponent's knowledge, and the rest of the play is a denouement where they wait out their inevitable death which could be what Dr. Strange referred to when he told Tony "we're in the endgame now". Also, there's the double meaning. The title is endgame and not end. Because there will be more movies after this and more Avengers stuff later. This is simply playacting about endings. It's simply making a game of ending the series and not actually ending it or to quote Marvel Comics' house philosophy since The '70s, it's not change, it's the illusion of change. This also fits with the Russo Brothers saying that the title would be a spoiler — the title "Endgame" spoils that, in Infinity War, most of the pieces on the chessboard were cleared off.
As pointed out on Reddit, Tony's situation is a Call-Back to Iron Man: stuck in an impossible situation and having to think of a way out. For bonus points, he's in practically the same attire, too.
Early on in the movie, when what remains of the team are planning their assault on Thanos, everyone is preparing for a difficult battle, only for Carol to point out that, last time, they didn't have her. When asked where she's been this whole time, her response is that there are a lot of planets out there, and none of them had the Avengers. When you think about that line, it adds a lot of depth to place earth and humanity have in the MCU. In comparison to alien species with Galaxy-spanning empires, mad conquerors who wipe out entire worlds, all wielding technology that makes what we can muster look like it came from the stone age, just what is it that Earth and Humanity bring to the table that makes them a thorn in the side of the likes of Thanos? Who was it that united a bunch of misfits into a force that was able to bring down the likes of Ronan the Accuser and Ego the Living Planet? Who was it that found the strength to oppose the Supreme Intelligence of the Kree? What does humanity have that's thwarted the plans of Omnicidal Maniacs and literal gods? The answer...humanity has people who, when all seems lost, stand up...people who spread hope and determination like a virus...people who call others to be more than the sum of their parts...humanity has heroes.
Near the beginning, the entire left half of Thanos's body is scorched and burnt, the right being unscathed. One half intact. The other debilitated. Just like his plans of a balanced universe. Thanos's philosophies have now made full manifest, as scars that will last for the entire rest of his life.
The concept of balance is reflected in Thanos' character in general: His massive spaceship has a central hub and two wings, he has an even number of enforcers (6) that also happen to be divided into 2 genders (Ebony Maw, Cull Obsidian, and Corvus Glaive are male. Proxima Midnight, Gamora, and Nebula are female). Finally, his weapon of choice is a sword with blades on both ends.note Also in the previous film, he gives young Gamora a weapon that has blades on both ends and demonstrates how balanced they are.
Early in the movie, Thanos says he's decided to destroy the Infinity Stones to avoid "temptation". Later, when his past self learns of "his" future accomplishment but also of the Avengers' ongoing attempts to undo it, he's immediately tempted to undergo an even more grandiose scheme. Indeed, the Thanos we loved/hated in Infinity War knew himself well.
Thanos and Tony's last words.
"I am inevitable" is Thanos'. It is what he thinks he is and he holds himself up in a high position because of this, showing incredible egotism. Despite his seemingly-sympathetic reasoning in Infinity War, Thanos reveals his true colours in Endgame as a selfish, maniacal nihilist, coming to the conclusion that because the universe will never be grateful for what he intended in his original plan, he would be better off making a complete clean slate of a universe warped to his own designs. He's wrong, he isnt inevitable because it wasnt a guarantee that in the end hell prevail.
"I am Iron Man" is Tony's. It's a point of pride like Thanos', but unlike Thanos, who is exaggerating himself, he is right and it is who he is. This is what he built himself to be, and it is something no one can take away from him. Note that the song "Iron Man" is about a man who traveled through time to witness an apocalypse, then goes back and causes it. Stark witnessed an apocalypse and traveled through time to undo it.
Fridge-Heartwarming: In a sense, Tony's lifestyle then ("Iron Man") and now ("Endgame") foil each other, making for a lovely book end to his adventure. Both homes are next to a body of water, and both are inhabited by Miss Potts, to a varying extent. But the Stark mansion reflected Tony's pride, arrogance, above-it-all detachment, and was only good for enforcing the bachelor life. His lake home, on the other hand, reflects his humility, selflessness, how down to earth he's become, and embodies the simple joy of married life and family. But both contain the high-tech tools necessary to fuel his inventive genius. No matter where he goes or what he does, he is Iron Man.
Given all the damage she has bounced back from in previous movies, it seems odd that past Nebula is killed by a single relatively small blast. Yet if one considers how it was present Nebula that did it, and Nebula knows her own body better than anyone, then she would know exactly where and how to fire a shot that could kill her.
How did Strange know just when and where to send The Cavalry? Well, knowing everything was basically his whole role in this and previous films — he knew, because it was part of the one perfect timeline he saw with the Eye of Agamotto.
Considering how you cant override the consciousness of your past self like in X-Men: Days of Future Past, its likely that while there is an elderly Steve Rogers present, there might also be another Steve Rogers who is still physically young due to the ice.
"The only thing you really fight for is yourself. Youre not the guy to make the sacrifice play." is Cap's insult to Tony. In this film, he fights to bring back those who were lost by the snap and is, ultimately, the one to make the Heroic Sacrifice to stop Thanos once and for all.
"Youre a laboratory experiment, Rogers. Everything special about you came out of a bottle." is Tony's accusations thrown towards Cap. Here, he debunks this by lifting Mjølnir with his pureness. Keep in mind, the serum played no part in this, as Mjølnir's worthiness enchantment is entirely dependent on the character of the prospective wielder. Even back when he was that ninety-pound, scrawny, asthmatic kid from Brooklyn, he would've been able to lift it.
Tony is easily the second most paranoid and Crazy-Prepared person in the MCU, beaten only by Nick Fury. It makes perfect sense that he'd equip the second Infinity Gauntlet with some sort of countermeasure that would allow him to quickly and easily strip the Stones from it if the wrong person, i.e. Thanos, is wearing it — which proves vital for his Heroic Sacrifice.
Alternate Guardians timeline:
By destroying a past version of Thanos and his Black Order before the events of Guardians of the Galaxy, the Avengers have removed his threat from another universe — there is now another timeline outside of the main one where Thanos no longer exists to put all Stones together and perform the snap, not to mention all the other species/peoples whom he'd slaughtered in recent years, such as Xandar and the remnant Asgardians.
By the same token, regardless of whatever becomes of the Orb of Morag, the Guardians are unlikely to come together, and Quill will probably never lay his hands on the Power Stone. Which means Ego won't ever seek him out, and his plans for universal unification will also, ahem, peter out. Alternatively, Steve could just allow Quill to get ahold of the Orb and let history run its course from there.
When he first returns to Earth, Tony bitterly remarks that they're called the "Avengers" rather than the "Pre-vengers" because they're always doing what needs to be done after the fact. By killing the alternate Thanos and his forces, Tony in a way becomes a pre-venger to the alternate timeline Thanos came from.
Before he was killed during the Snap in Infinity War, Strange solemnly tells Stark that "there was no other way" to ensure Thanos' defeat. He is not talking about the Snap itself, but Tony's Heroic Sacrifice.
He tells Tony a bit earlier in Infinity War that he wont hesitate to sacrifice Tony and Peter if it comes down to it. Ultimately the plan does come down to sacrificing both Peter and Tony. The former as part of the snappening when he gives Thanos the Time Stone and the latter five years later when he has to sacrifice himself to kill Thanos.
Further enforced by Strange's next two interactions with Stark — the first, he tells Stark that if what needs to happen is said out loud, it wont happen; and the second comes just as Stark is about to use the Stones and expecting it cost him his life, when he looks over to Strange for confirmation that this is the one outcome when Thanos is defeated.
On a more mundane level, Strange also knew that surrendering the Time Stone to Thanos without more than a token fight was the only thing that would ever convince the Ancient One to hand it over to the Avengers in the past. So his last pre-Snap words to Tony also encompass his own passive forfeiture of the Time Stone: had he fought to the last, all of Bruce's words to Strange's mentor would've been futile.
Somewhat Heartwarming in Hindsight, Strange likely also bargains for Tony's life for two additional reasons; He saw that Tony would start a family with Pepper after the Snap, therefore giving him something for him to live for before his sacrifice. Second, dying at Thanos's hands, in despair at failure, or dying by protecting his Avengers teammates, his new family, (including a surrogate son in Peter Parker, whom he just got back), and the world, surrounded by loved ones? Strange chose the latter to be as humane as he could be given the situation.
After using the Stark-tech "Infinity Gauntlet" once, Hulk gets seriously burned and unable to do much in the actual climax, because Hulk needs his rage to trigger his Required Secondary Powers like his Healing Factor.
Professor Hulk seems smaller next to the other actors than Savage Hulk, and this is especially noticeable in the 2012 sequences where you can see both Hulks near each other (Savage Hulk seems One Head Taller than Professor Hulk). Bruce may have successfully merged himself and Hulk, but it comes at the cost of some of Savage Hulk's raw, rage-fueled power.
Thunderbolt Ross attends the funeral of Tony and doesn't seem to have a problem with the fugitives in attendance. Could it be he recognises they saved the world again after 5 years of the Snap, or was it gratitude for another reason? His daughter Betty was confirmed to have been lost due to the Snap and they brought everyone lost back. There's also the possibility that the Sokovia Accords were repealed after the Snap. Since apparently Thanos's name is well-known on Earth, it's extremely likely that the governments of the world (the surviving ones, at least) enacted official inquiries into just exactly what caused the Snap, and what everyone's role in the event was. Since the disintegration of the Avengers could be directly traced to the Sokovia Accords, and the very nature of the New York and Wakanda incursions would not have allowed the UN to coordinate a response in time, it's almost certain that the Accords were indeed repealed for being pointless before (indeed, for having caused much more harm than good), and being utterly meaningless in a post-Snap world.
Thanos's speech about what it's like to lose comes back as an Ironic Echo for himself this time around.
Thanos believed he was in the right, and had to kill half the universe, but fails due to the Avengers. (To feel so desperately that you're right, yet to fail nonetheless.)
He can only stand by and watch in silence as his armies are erased by Tony's finger snap, just like everyone he killed himself. (It's frightening, turns the legs to jelly.)
In the end despite everything he did, Thanos met his ultimate fate. To be defeated by the heroes at the end of the story. (Dread it. Run from it. Destiny arrives all the same.)
Why is the Ancient One surprised that Strange gave Thanos the Time Stone, despite knowing about him? She is unable to see events that happen after her death, as mentioned in her final conversation with Strange. This probably also heavily factors into why Strange went with this plan. Many of his failed timelines likely included Thanos killing Strange; whatever happened past that point, Strange would not know. Surrendering the Stone opened up timelines where he could see past that battle. All he needed to do then was narrow it down to timelines where "Strange dies in the Snap but is returned to life" and parse through those for a victory. Indeed, narrowing his search down to ones where he's Snapped and later un-dusted is probably why he only had to look at millions of timelines, rather than billions. It'd only be a very small fraction of possible futures in which the un-snapping took place.
There are certain character parallels between Infinity War and Endgame, that sometimes act as foreshadowing for what's to come. For example, Black Widow and Gamora are noted to be counterparts to each other — one girl on a team full of guys, dark pasts where they were raised by morally dubious people, etc. Meanwhile, Hawkeye-as-Ronin, when asked by a member of the Yakuza why he's killing them all, gives a reply that's along the lines of "half of the universe got Thanos. You get me," effectively comparing himself to Thanos. If you keep these parallels in mind when you watch Clint and Natasha go to Vormir, then it becomes obvious which one is going to be the Human Sacrifice and which one will leave with the Soul Stone.
Thor's reaction to Cap lifting Mjölnir is to jubilantly declare "I KNEW IT!" — which would mean his shocked reaction in Avengers: Age of Ultron when Cap only managed to slightly budge the hammer wasnt because he may have been worthy, but rather because he wasn't at the time.
Or that "budging" Mjölnir shouldn't be possible... one either is worthy, or one is not. Whatever it was that made Steve Rogers "barely" unworthy has been cleared up.
Steve may have become worthy of Mjölnir after the events of Captain America: Civil War when he finally had to deal with the consequences of Bucky's complicity in the deaths of Tony's parents.
Alternatively Steve was worthy at the time of the party, but saw how shaken Thor was at the thought, and chose not to lift the hammer. He could sense he could lift it, but didn't want to show off and... steal Thor's thunder. (Sorry. No, I'm not.) Plus Thor has had time to reckon with the hammer in new ways since that scene, so his attachment to being solely its wielder and worthy of it has changed after the events of Ragnarok.
Or Mjölnir just didn't approve of being used as a party trick.
Or, Steve, being Steve, didn't believe himself Worthy. Perhaps part of being Worthy is accepting your own Worth. In the comic book is explicitly stated that to be Worthy you must feel worthy. Comic Book Thor ended up losing his Worthniness for a lenghty time because he started doubting himself and the outcome of his choices. Being that Cap is the ultimate Humble Hero, the only time in which he doesn't actually doubt his worthiness and his choice is when he's too busy sacrificing himself for the others.
One possibility is that it was Natasha's sacrifice that made Steve Worthy. He's the one who voices the realization that the Avengers were her family, and he probably comes to a similar conclusion about himself. Putting his "man out of time" doubts about his place in the world to rest and fighting to save his chosen family is easily enough to bump him over the line into Worthiness.
Another possibility is that the Steve of Endgame was a man willing to fight and retire. In Age of Ultron, Steve's mind was still in the war, as the vision showed he was always looking for another war. At the end of Endgame he was also finally willing to stop fighting, be with the woman he loved, and let Falcon take up the shield instead.
Word of God has since stated that Cap was always capable of lifting the hammer.
Cap being able to lift the hammer also establishes him as the only candidate (after Thor left Earth) to return it (and the Infinity Stones) to its proper place on the timeline.
Sanctuary and Captain Marvel:
Why does the Sanctuary stop firing on the heroes and focus on Carol instead? Well, as previous films have established, major players in the cosmic MCU seem to know about each other even if they have very little interaction. Thanos and the Asgardians know about each other, the Asgardians knew the Collector, and Carol seems to have known about Thanos. Given that Carol has spent the 20 years between her solo debut film and the present flying around the universe helping those in need, in particular having saved the Skrulls from extinction, it's not a stretch to assume that as a result Thanos knew about her.
Thanos's mooks aboard Sanctuary II probably detected her energy signature entering Earth's Atmosphere and heading right at them sooner than the heroes did. Even if they didn't know her, they realized that they were in such great danger that they decided to fire at her risking the consequences of disobeying the Mad Titan himself.
Ronan is already Thanos's associate at the time Sanctuary II came from, so Ronan may have told Thanos and his associates about his fleet's one-sided encounter with Carol Danvers a few decades earlier.
It might seem strange that Hulk is being hurt by the Infinity Stones when using the Stark Tech gauntlet while Thanos was simply infused with their power and was fine. This could be because Tony doesn't know how to build something to handle that much or that kind of energy. The Infinity Gauntlet was specifically designed for the task, and the dwarves have a lot of experience designing weapons and artifacts for gods.
Additionally, in Infinity War Thanos took his time setting each Stone into the Gauntlet, and adapted to the power increase every with every new addition. Banner took on the full Gauntlet all at once, and his, ahem, bulk as Professor Hulk is noticeably smaller than the original Hulk's, so the immense power surge burned him up immediately. At the same time, 2014 Thanos put on the full Gauntlet twice, and both times he was stunned for much longer than he was in IW, and didn't adapt, either. Tony, meanwhile, was likely protected from the worst of the backlash by the Iron Man suit, at least until his own Snap.
If they brought back the empty gauntlet from Thanos's garden, Tony could have studied it to recreate the design needed as close as possible.
It could also be possible that Thanos simply is more resistant to gamma radiation, as Hulk says the radiation the stones emitted were gamma rays. The Hulk, while being about as bulky and gamma radiation resistant as Thanos, still is a human and, thus, still vulnerable to too much gamma radiation.
Being made from Stark Tech nanomachines, it would make sense that Tony could easily transfer the stones from Thanos's hand to his without Thanos knowing about it. When did this happen? If you listened closely, mechanical sounds could be heard during the brief moment Tony got his hands on the Infinity Gauntlet.
Note that both Tony and Steve have been subjected to nigh-unendurable amounts of energy that wracks their bodies: Steve, when he received the serum that first made him Captain America, and Tony, when he performed the final Snap and ended his life as Iron Man. Their respective sufferings serve as Book-Ends to the entire Infinity Stones story arc. Not only that, but Thor and Banner also willingly suffer their own painful energy-overloads in the course of the two Thanos films: Thor, to channel the power required to forge Stormbreaker, and Banner, to perform the Unsnappening.
Another aspect of their Hourglass Plot: their entire arc is coming full circle. Tony was a selfish man who started out dying. Steve was a selfless man who started out in the 1940s. Tony's story ends with him dying from the Infinity Gauntlet, only this time he's far less selfish than he was in that Afghanistan cave. Steve's story ends with him back in the 1940s with Peggy because, thanks to Tony's advice, he decided to think about himself for once and be with the woman he loves.
Tony running the time-travel simulation, just to prove that it's not possible (and then discovering that it totally is possible!) Once an idea gets in Tony Stark's genius brain, he can't just let it go, he has to follow up on it. He did it tinkering with his engines, he did it designing weapons, he did it making the Iron Man armors. It almost makes you wonder if Steve or Natasha knew that all they had to do was put this idea in Tony's head, and sooner or later he'd make it a reality, even if he didn't want to.
Steve and Bucky's parting words to each other mirror those from when they said goodbye during World War 2, a time when they knew they would not be seeing each other again for a long time. This implies Bucky knew what Steve was going to do (live another life with Peggy) and they had in fact already discussed it. This also explains why he's not surprised and is the one to point out where the elderly Steve is.
The Soul Stone can only appear when you sacrifice that which you love. Why, then, would Clint receive the Stone, when he was doing his very best not to let Natasha die? Red Skull specifically said that one must "lose that which they love". No mention of personally killing anyone which allows for a broader interpretation. Natasha sacrificed herself, thus causing Clint to lose her and gain the Stone.
Thor's rather depressive state much throughout Endgame proved to be somewhat divisive with viewers, but makes sense when you consider that the events of Thor: Ragnarok and Infinity War happened in extremely close proximity to one another. In short order: Thor has had to cope with the death of his father Odin; learning that Asgard was built on Odin and Hela being bloody conquerors; Hela cutting out his eye and destroying Mjölnir and taking over Asgard for her own; having to allow Asgard to be destroyed to protect his people; having to witness half the Asgardians under his watch get massacred by Thanos; watching Loki, the last of his family, and Heimdall, one of his best friends, get killed before his eyes; and finally, Thanos erasing half of existence across the entire universe because Thor failed to aim for his head.
In addition, since Asgardians' alcohol tolerance is much higher than that of humans, Thor must've been drinking absurd amounts of alcohol to such an extent that Thor downs several kegs of beer in a month just to get buzzed. Thor tried to drown himself in alcohol just to forget the horrible events that had happened to his life.
The elderly Steve Rogers at the end tells Sam he doesn't want to talk about who he married. For the audience, it's obviously done so the ending scene will reveal he went back to Peggy in the 1940s. But in-universe it seems weird that elderly Steve doesn't want to talk about his wife. Why not? Well, because Peggy developed Alzheimer's, and her death would still be recent. Elderly Steve doesn't want to talk about it because he's still grieving over her death!
A minor one compared to the other entries here, but Thor's unfamiliarity with earth customs very likely contributed to his transformation into an alcoholic slob. As he could no longer return to Asgard, he likely just asked someone what they do when they're feeling down, and they just happened to answer Fortnite. He's still playing it in 2023, so there's a good chance he doesn't even know other games exist. Although to be fair, in a post-snap world it seems unlikely that there would be many more games being produced, so Fortnite could still be one of the newer games even five years later — it's implied that things like sporting events don't really happen anymore, so obviously recreation is a much lower priority now.
In "Infinity War", Thor says weapons like Stormbreaker have the power to drive anyone not powerful enough mad. Stormbreaker doesn't drive Thanos mad when he uses it to try to kill Thor not only because he's exceptionally powerful, but because he's already the Mad Titan.
Now how exactly did Tony get all of the Infinity Stones from Thanos' Gauntlet without him noticing? The Gauntlet Tony built is based on the same technology as his nano-suit, allowing it to reshape itself as needed by moving parts around. Tony's suit interfaced with the Gauntlet and had it move the Stones onto him instead.
Why would Steve give the shield to Sam? Because he knows his friends so well. Bucky was pretty happy living at peace in Wakanda, and as T'Challa commented in Infinity War, "This one has seen enough of war." After all the darkness of his past, Bucky just wanted to rest and be done with heroing. Sam however was working with Cap during the two years of exile. He took up the Call to Adventure and never looked back to fight with his friend as the Falcon. And if that's the case, then it would make sense that Steve would pass the mantle to the one who would carry the shield with passion.
Sam also has another similarity to Steve: when he was done fighting, Sam became a counselor attempting to help others get over their trauma, but doesn't hesitate to rejoin the fight when it's time. After the Snap, Steve does the same. It's entirely possible that just as Sam was inspired by Steve, Steve was inspired by Sam.
Doctor Strange tells Tony that if he were to inform him about the future he saw, it wouldn't come to pass. Strange is proven right by 2014 Thanos, who saw his future of acquiring the Infinity Stones in Nebula's memory drive, then proceeded to do everything in his power to speed up the process. What happened? He failed. He was no longer inevitable.
Thanos succeeded in Infinity War because of his willingness to sacrifice everything, including his beloved daughter and all of his loyal forces, whereas the heroes failed partially due to their unwillingness to "trade lives" as Steve put it. Five years later, the surviving Avengers are resolved to do "Whatever it takes" to bring back the people they lost to Thanos. Natasha sacrifice herself to obtain the Soul Stone, (with Clint willing to do the same), and Tony is willing to give up a Happily Married life with his family, and then ultimately his life, sacrifices that lead to them finally succeeding.
2014 Thanos seems to be a lot more arrogant and less sympathetic than the one in Infinity War. This seems odd, until you consider that Infinity War Thanos had to sacrifice Gamora to get the Soul Stone. This sacrifice may have humbled the Mad Titan, reminding him that he can still feel pain and loss. 2014 Thanos didn't have to go through this, so he is still as arrogant as ever.
Meta example: This was Stan Lee's final MCU cameo, so the fact that it's accompanied by the words "'Nuff Said!" is fitting.
Captain Marvel in the climax:
Carol can take multiple hits from Thanos, who had been able to overpower the likes of Thor and Hulk at various points in time, and she also takes multiple shots from the Sanctuary II without pausing, yet one blast from the Power Stone is enough to put her out of commission long enough for Tony to be forced to pull a Heroic Sacrifice to prevent the worst from happening. Initially, this can come off as a too-convenient shot to maintain drama, until one remembers where Carol's powers come from: the Tesseract, a.k.a. the Space Stone. It's been made clear multiple times that an Infinity Stone can defeat another Infinity Stone, so it makes perfect sense that a point-blank blast from the Power Stone would put Carol down for a while.
A much simpler explanation: She was hit with the Power Stone, an artifact which in GotG was said to be capable of one-shotting the population of the entire planet. Considering she isn't seen for the rest of the battle, that punch may well have sent her into orbit.
The trashed-up, messy, and outright dystopian view of the world after the Snap isn't just the result of depression; it's also the result of supply-lines, bureaucracy, and infrastructure across the world all being crippled by the loss of life. This exposes a major vulnerability to Thanos's original goal and proves yet one more way he was disastrously misguided: the world is an even more dangerous place now because society is severely wounded, and while some things are on the up-and-up, the average Joe Schmoe is at just as much risk of dying from deprivation as he was before, if not more so, if the supply lines he depended on were destroyed. This is why other planets are in such terrible shape that Captain Marvel is kept busy away from Earth, and why criminal syndicates were even more likely to raise Clint's homicidal ire: unless support system members (like the remaining Avengers themselves) survived in large enough numbers to continue helping people, the deprivations of natural disasters and predatory exploitation by criminals will hit devastated communities even harder. Imagine if FEMA lost so many staff they couldn't respond to a hurricane properly, or if the Cartel and Yakuza Clint targeted were in an area where cops had taken an uneven number of losses.
Bruce couldn't bring Nat back from the dead while undoing the snap. Two possible explanations exist other than the "Soul Stone sacrifices cannot be returned".
If the theory that the Soul Stone stores the soul of whoever was sacrificed is true, he couldn't bring her back because she was still alive, just in a different form inside the Stone.
She died in another timeline, and as far as we know, the Stone's powers are limited to whichever timeline they're used in.
Doubles with Fridge Horror: Bruce could only bring back, despite his best effort, people dusted away from the first snap. An untold amount of people died because of the later consequences, such the Universe turning into a messy dystopia requiring the Avengers to work 24/7 to keep everything working and Captain Marvel, Nebula and Rocket roaming planet to planet bringing relief: they're not going to be back.
Another way of looking at it is that he didn't think to bring back anyone who had died by proxy of the Snap or thought that the undusting was too risky as is to try it.
It makes strategic sense for Thor to be insistent that Steve uses Mjölnir rather than Stormbreaker. Mjölnir explicitly grants its wielder "the power of Thor". Thor already has the power of Thor, so if anyone else is capable of wielding it, it's better for them to do so, so there can be twice as much power of Thor. Moreover, Stormbreaker is a two-handed axe, and Cap can't use it as effectively while wielding his shield.
When Scott asks if either Cap or Black Widow have studied quantum mechanics, Natasha says "only to make conversation." Which would make sense if she was trying to have something to talk to Bruce about and get him to notice her.
Likely a coincidence but having there is another reason why the sound of Tony's hammer striking the Mark 1 helmet was chosen to be the post-credits "scene" aside from being the MCU's progenitor. In the scene itself, he struck the helmet 11 times, one for each year from Iron Man (2008) to Avengers: Endgame (2019).
Thor's character arc mirrors Valkyrie's in Thor: Ragnarok. When we first meet Valkyrie, she's a depressive alcoholic willing to just passively let something horrible continue on, declaring she wants nothing to do with her past. Gradually, she realizes that her people need her, faces her greatest fear in Hela, and boldly reclaims her Asgardian identity. Meanwhile, Thor is put outside of his comfort zone and must learn to be a leader. Now, Thor's depression and trauma has made him all but renounce his role as king, compelling Valkyrie to take charge and look over her people in their greatest crisis yet. By literally revisiting the past and finally getting closure with his mother, Thor strikes a balance between doing right by his people and himself, realizing that the king's role doesn't suit him either. In the end, he appoints Valkyrie his successor and goes off with the Guardians of the Galaxy to realize just where in the universe he belongs.
While Asgard was ostensibly a planet, most of what we seeresembles Northern Europe. While rabbits are native to Europe, raccoons are North American. No wonder the Asgardians call Rocket a "rabbit", that's the only context they have for his type of mammal. "Badger", "fox", or "weasel" could work better, actually, but it's true that they'd have little or no familiarity with raccoons. Although, who knows? Maybe the kind of rabbits they had in Asgard walked around on their back legs a lot.
Back in Infinity War, Doctor Strange said if he had to choose between saving Tony and/or Peter, or protecting the Time Stone, he would let them die to protect it. While we find out later he handed it over because the only way to defeat Thanos was by having him do the Snap and then Tony sacrificing himself to undo it, it makes Tony's actions in a way a form of irony. Tony was willing to put his wife and daughter above getting the Stones back, but in the end put the importance of using them to stop Thanos ahead of them. In effect, they both ended up going the opposite of what they claimed in order to defeat Thanos.
It seems like Fridge Logic that the two Avengers who are sent to Vormir to get the Soul Stone just so happened to be the two members who cared very much for each other that they are both willing to sacrifice themselves so the other could live. Remember that Doctor Strange said that he had seen over 14 million possible variations of the outcomes. A large number of these variations are most likely the cases where the surviving Avengers send the wrong team to Vormir and not Clint and Natasha, which resulted in failure to get the Soul Stone and thus they can't undo the snap. The timeline we've seen in the film is the only one where they got it right, as well as everything else that comes after that so they finally achieve victory.
In Captain America: Civil War, Tony is lying on his back when Cap slams the shield down. Tony uses his arms to cover his face horizontally, allowing the more experienced Cap to hit the Arc reactor in Tony's chest, neutralizing him. In Endgame, Tony is in a similar situation, but blocks vertically, allowing him to defend both his chest and his face at the same time. In all things, Tony is Taught by Experience.
Pepper outright encourages Tony to aid the Avengers in undoing the Snap. This is despite her wanting him to quit, even leading up to their temporary breakup in Civil War. Why the change?
She, unlike Tony, was on Earth when the Snap occurred. She had a first hand civilian view of the terror that erupted through society at the time.
Keep in mind that we don't see Happy Hogan, one of her and Tony's closest friends, until the end at Tony's funeral. Odds are that Happy got to Pepper to protect her when Thanos' forces initially invaded, and she likely witnessed him getting dusted. Tony's not the only one that has people they'd want to bring back.
She also has had five years to think on the context of what Tony, and by extension, the rest of the Avengers have gone through and wanted to prevent and protect the world from.
She likely knows about Peter's influence on Tony, and now having a daughter herself, is putting herself in Tony's shoes, therefore would want to gain her daughter back if the situation were reversed.
As much as she doesn't want her daughter to grow up without a father, she really doesn't want her daughter to grow up knowing that the bad guys win.
Tony has a photo of himself and Peter. Peter is usually at some point, depicted as being a photographer for the Daily Bugle. It's a subtle reference.
In a sense, Thanos received karma for what he did to Vision. How? Let's go over the numbers:
Vision originally died on his own terms, sacrificing himself by allowing Wanda to destroy the Mind Stone, dying with the satisfied thought that he'd be saving the woman he loved. But thanks to the Time Stone, Thanos reversed his fate and gave poor Vision an alternate death, where he dies with his Mind Stone stolen by Thanos and knowing he somehow failed to save Wanda and humanity as a whole.
The original Thanos initially died on his own terms, killed by the Avengers, but knowing he'd already created a "thankful Universe" and was content to know his work was done. After the Time Heist that accidentally brings Past Thanos to the future, Tony bestows the same fate to the Mad Titan: he dies an alternate death, turning to dust with the knowledge he somehow failed to triumph in his conquest
Why wasn't Vision rebuilt in some form since in the Timeskip? Because Shuri (likely the only other person smart enough to do the job) got dusted and her lab where she was building him was attacked and damaged by Corvus Glaive. Also, they'd lost the Mind Stone base used to create him, and his forehead was ripped open by Thanos. Wakanda would have been more focused on helping out in the aftermath of the Snap rather than rebuilding him when they didn't know how to do so. It's basically an unfortunate combination of all these factors.
Professor Hulk is chosen to perform the initial Snap to restore all the people over Thor. The thing is; Thor's smart, but not Genius Bruiser level smart like Thanos. It's apparently better odds to be powerful mentally and physically, and Banner's new fusion is just that.
Also Thor had been drinking throughout the entire movie and he decided to talk to his mother rather than follow the plan to get his stone back. Trusting a probably drunk man who has already shown to be currently unable to follow instructions with an object that could break the universe is not a great idea.
There are an awful lot of Sorcerers in the final battle against Thanos, more than we're led to believe exist in Doctor Strange (2016). But this is post-Snap... how many people were left without a purpose in life? Teachers without students, doctors without patients, sports fans without sports... how many people went looking for something new to give their lives meaning, and found Kamar-Taj? And unlike Pangborn, who took his miracle and walked away, these people would understand exactly why the world needs more Sorcerers.
When Bruce tells the Ancient One that Strange gave the Time Stone to Thanos, she's shocked, stating he was supposed to be the best. Bruce states that maybe Strange made a mistake, and the Ancient One melancholically replies "Or maybe I did." Made a mistake thinking Strange could be her successor? No. Made a mistake not trusting Strange's chosen allies. If the Ancient One trusts Strange to succeed her as Sorcerer Supreme, then she should trust the people he trusts.
While Clint compares himself to Thanos as Ronin, he is actually more like Ronan. Ronin and Ronan sound phonetically the same. As Ronin, Clint is essentially doing what Ronan was doing, killing those he accused of being guilty. By associating himself with Thanos, Clint is playing Ronan's role.
Tony defeats Thanos by swiping the stones off the glove while Thanos isn't looking and then responding to Thanos' boast with his own. In other words, a cheap trick and a cheesy one-liner.
The Ant-Man inspired part of the film, the Time Heist, involving a team trying to pull off a dangerous heist using Pym Particles and something going wrong.
Thanos' armor is being used as a scarecrow in the beginning because that's what it is. At that point, Thanos is a shell of his former self and not a threat because he had just used the Infinity Gauntlet to destroy the Infinity Stones, crippling himself. At that point, the armor is just a symbol or a front for the terror he used to bring, not for the power he doesn't have anymore. Like a scarecrow, Thanos brings terror to anyone who sees or hears about him but he is actually not a threat anymore.
Some fans note that in this film, Thanos seemed more durable and able to deal more punishment than in Infinity War, despite having the Infinity Gauntlet. However, when one sees how the Gauntlet burned both Hulk and Iron Man simply by being worn, then the implications set in; Thanos was physically weakened by the damage, but being significantly more powerful than either of them, it was less visible. He also wasn't wearing his armor at the time, which may have also contributed to the extra damage racking up.
This also explains why he didn't use the Gauntlet's powers to just nuke the heroes when given the chance; he didn't want to burn himself out before he could finish the Gauntlet and perform the snap.
When Thanos was whacking Cap's shield and broke it off, I personally wondered how that could be if it was a vibranium shield. Then I remembered; Vibranium came from a meteor. It's not hard to believe that there are other planets or asteroids that have their own vibranium deposits. And since Thanos has a massive galaxy-wide empire, finding said resource wouldn't be too hard, and considering how he manhandled Black Panther he probably didn't have any trouble getting said metal either. Moreover, Vibranium is the strongest metal on Earth. There could be stronger metals out there in space that can easily break Vibranium, and Thanos' sword is made from said metal.
Why is Steve finally retiring? Because part of his will to fight is that he knows he can't go back in time and be in a relationship with Peggy. However, once time travel is possible and he sees Peggy in the past, he knows it's possible to finally stop fighting and settle down with the woman he loves.
A simple one, but Thanos' motives required him to sacrifice everything and everyone near to him because he felt it was his destiny. He is defeated by Tony choosing to sacrifice himself to save everyone and everything but himself, not because it was destiny itself, but because it was ultimately what he felt was more important.
When Tony swipes the Infinity Stones from Thanos and performs his Heroic Sacrifice, he doesn't do anything more than dust Thanos and his army. Why is this significant? Because this is the same Crazy-Prepared, Properly Paranoid man who, even at the beginning of the movie, was yelling at the remaining Avengers that he was right and they really did need a suit of armor around the world to protect the Earth. That was AFTER his exact plan for that reality, Ultron, went south hard. Yet when he gets probably the biggest chance to implement some grandiose, grand-standing plan and altering the world with the Infinity Stones to protect it, he doesn't take it. Even Banner when he unsnapped everybody tried to extend the scope of his snap to include bringing back Natasha. But here, Tony only does what it takes to end the fight and ensure that Thanos never succeeds. Why? Well, in addition to likely having more faith in the Avengers to protect the earth on their own considering they were able to bring a LITERAL ARMY against Thanos's, he also probably saw a bit of himself in Thanos. Thanos had a plan that sounded insane, but that he himself believed was right and saw through to the end. Tony's character came full circle and he accepted that he might be well-intentioned with any plans he could cook up, but just like Ultron, could turn out to be failures, and he knew he wouldn't be around to right any wrongs this time. He dropped the last of his ego and arrogance and only did what he needed to do, and nothing more. He was finally letting go of his paranoia and pride and trusting in the team like Steve said all those years ago.
The song "It's Been a Long, Long Time" isn't just symbolic of Steve and Peggy's joy in being able to finally be together and live out their lives in peace, it's reflective of the feelings of everyone in the galaxy after the people who Thanos snapped got restored. Lines like "Never thought that you would be/Standing here so close to me" and "Haven't felt like this, my dear/since can't remember when" really reflect how so many people must have felt, after five years of grief, hopelessness, and desperately trying to move forward, and suddenly seeing the people they loved and lost in front of them again. It's not just a love song for Steve and Peggy in this movie, it's one for the whole universe.
Rocket randomly talking to Scott Lang and petting him like an animal may just be Catharsis Factor at work, as Rocket has lived among Earthlings for 5 years, where unlike being around just Peter Quill, there's an entire civilization mistaking him for a furry little animal until he opens his mouth.
Natasha's Heroic Sacrifice is also actually that of a Mama Bear moment for her. She physically can't have children, but her closest friend, Clint, does, and his kids even refer to her as "Aunt Nat." This is the closest that she believes that she'll get to having children so she makes the ultimate sacrifice to get them back.
Dr. Strange not telling Tony whether or not they're in the winning timeline until the last moments makes sense because if he did confirm that they would win, then Tony (and most likely the other heroes) would be confident enough to let their guards down and allow Thanos to turn the tables on them. In addition, if he told Tony right then and there that the condition of their victory meant one person had to die, then Tony (and the other heroes) would most likely hesitate to allow one of their own to make a Heroic Sacrifice and allow Thanos to turn the tables on them. In a meta way, Dr. Strange not telling the ending to Tony is the equivalent of him not spoiling the ending of the movie.
During all of the TV Spots, the flashbacks to Infinity War were solely in black-and-white, except for the parts which were red - those retain their color. At first, this seems to pay tribute to how the casualties turned to dust (monochrome), which is metaphorical for blood being spilled (red). However, after the movie, it becomes obvious that the dusted heroes aren't the only thing these spots are paying tribute to - these were in tribute to the actual casualties of the two movies: Iron Man, who has red armour; Black Widow, who has red hair; and the Vision, who has red skin.
Captain America's story began before the end of World War 2, as he hunted the Tesseract and, in order to save the world, left Peggy Carter, missing out on a dance with her. His story ended after the end of World War 2, as he put the Tesseract back in its rightful place and, after saving the world, rejoined Peggy Carter, finally getting that dance.
While the implications raised of the Time Heist's fallout by fans (Steve pretending to be part of Hydra, Gamora not being around to form the GotG) are concerning, there's something that hasn't been mentioned: the events of Steve's final time trip. Put things back in the 1970s, fix the Hydra and Loki problems in 2012 using the scepternote Loki would've been vulnerable after the Hulk, head to the alternate 2014 timeline to help form the GoTG with the help of Captain Marvel to handle Ronan and Ego, and go to 2013 Asgard to return Mjølnir before heading back to the 1940s.
Assuming that the closing scene in "Infinity War" where Thanos speaks to Gamora's soul in the Soul Stone was NOT a figment of his imagination, that means Thanos knowingly destroyed Gamora for a SECOND time when he destroyed the Infinity Stones.
Considering Luis' van got put into storage by the time Scott Lang came out, Luis did not retrieve his van, which could only mean he did get snapped out of existence.
Steve returned all the Stones back to their proper place in the timelines. That means he had to go to Vormir and possibly meet the Red Skull once again...
The Ancient One states that without any of the Stones a timeline is not able to protect itself from other threats. This makes sense as in the film Doctor Strange they only won against Dormammu by using the Time Stone. In order to ensure these other realities are safe, the Stones must be returned. This leaves the main timeline with no Stones though as Thanos destroyed them, and with no Stones no way to protect our reality from future threats like Dormammu. The Soul Stone being destroyed also means that Red Skull has no stone to keep. Hopefully the now-immortal and superpowered stonekeeper has mellowed out enough to remain on Vormir.
Since Spider-Man: Far From Home takes place after this movie and MJ, Ned, Betty, Liz, Flash, Abe, Cindy, and Sally are still Peter's classmates and not five years older, this means that they all were snapped. Assuming their parents weren't, this means that for five years their parents were grieving for their dead children, and possibly were there to see their children turn to dust. Imagine Adrian getting a prison visit from his wife only for her to tell him what happened to Liz.
If Thanos ended up killing micro-organisms with the snap, imagine all the people suddenly re-developing nasty diseases that had previously just vanished for no reason, and are helpless to stop them?
Think about how much Adult Fear people in our own world go through if they lose track of their kid at a shopping mall or the market, and can't immediately find them. Even if the child turns up right away, the fear that they were kidnapped, got lost, or ran out into traffic can be petrifying. Now, imagine what it'll be like to lose sight of any loved one, when you know they could potentially have fallen to ash while your back was turned. It's going to be months before people like Clint can bear to let their families out of sight without feelings of panic; indeed, it probably took months during the time-skip before many survivors could bear to be parted from their families, for fear the Snap would happen again.
Some of the people who were Snapped may have been near death from illness or old age. So when the Snap was undone, their loved ones would get them back for only a short time before they died, thus losing them again. A silver lining might be that at least they might have some more closure this time.
Snapping half the universe (dead or alive) was enough to cripple Thanos and Hulk's arm in the process. 2014 Thanos wanted to use the Stones to not only kill all life in the universe, but start it anew entirely at his whim, likely not knowing of the insanely high personal risk of doing so. How far would he get before the power kills him? We could've ended up with a completely dead universe.
All the people who were brought back by the Snap have missed out on five years of the lives of their loved ones; children have grown up, older relatives or friends have died, at least some partners or spouses have probably moved on and met someone else. There's going to be a lot of confusion and heartbreak. This can be even worse if loved ones died as a consequence of the Snap, by unmanned vehicles, lack of available donors, or even suicide.
Rocket has now been without his family for more time than he ever got to spend with them in the first place. He's clearly grateful for their return, but the emotional scars from that long, long period aren't the kind of thing that just disappear. It's likely going to put some serious strain on the relationship between him and his friends going forward.
In Guardians of the Galaxy Rocket mentions he "doesn't have that long a lifespan" indicating his cybernetics don't do anything to increase his life expectancy. Raccoons in captivity can live for around 20 years which means his fellow Guardians have been dusted for a quarter of his natural life and, depending on how long he was active prior to the first film, Rocket may only have a couple years left before he expires.
Speaking of confusion, the legal issues that are going to happen due to about half of everyone literally not existing for five years and laws passed in the wake of the Snap to deal with that issue becoming irrelevant are going to be nightmares. At least the lawyers are going to make bank trying to figure out ways to rescind wills and property transfers, figure out if life insurance needs to be paid back, marriage licenses....
Some alien species' natural lifespan could be less than five years, or five years would be a large chunk. How many would have been brought back with no-one left to remember them.
It's shown that the entire royal family of Wakanda was snapped. How many other countries had their heads of state snapped away? There easily could have been power vacuums that led to violent revolutions and revolts. Imagine coming back after those five years to find your country in ruin because of this.
In the five years since billions of people disappeared, food production probably went down significantly. Same with other products. While Tony's Snap will also bring back cattle, crops, and farmers, it won't bring back all the working infrastructure that has been dismantled or unused for 5 years, particularly tractors and other farming machines as well of container ships, harbours, trucks, airplanes, and other logistics. It will probably take substantial emergency measures of governments, NGOs, and the UN on an international scale to harvest and transport more food to all of the returned people and prevent a famine.
In order to prevent the alternate timeline they use to get the Stones back from being distorted, they return the Stones back to their previous place. Except they did more to these other timelines than borrow the Stones:
Alternate Guardians of the Galaxy timeline:
They knocked out Quill and took Gamora and Nebula out of the timeline, along with Thanos and his forces.
This would prevent the formation of the Guardians of the Galaxy. Without Gamora and Quill presumably not getting the Stone as Ronan would have beaten him to it, there would never be a reason for them to form.
With the Power Stone returned to its proper place, there wouldn't be anyone to stop Ronan from destroying Xandar and any other planet he deems fit to destroy with it, and even Captain Marvel.
And also, with no Nebula and Gamora, the vital role they played in foiling Ego's plans for Peter (and the entire universe) wouldn't be fulfilled.
And, without Thanos, the Stones would still be in-play to be used by whomever chooses to seek them out, and who's to say this someone isn't far worse than Thanos and without his attack to unite them together again, the Avengers are not in play to prevent it.
Alternate The Avengers timeline:
They freed Loki and had no way of tracking him down, which forced them to go back earlier to get the Space Stone, but nothing says they were able to get him back, which would indicate he never got to undergo his Character Development and HeelFace Turn.
Loki disappearing with the Space Stone would have affected tensions with the secret HYDRA sect within S.H.I.E.L.D. and the Avengers, which would have completely unknown effects on the former's plans or the populace's opinion of Thor.
The Space Stone is also now gone with only Loki to either protect it or hand it straight to Thanos.
Hydra also now thinks Captain America is on their side. But some communication with higher ups would prove the main timeline Cap's story false. Hydra would then get paranoid that Captain America is onto them and may cause them to try and kill their timeline's Cap before Winter Soldier.
"Steve reunited with young Peggy Carter" timeline:
Steve is the only one to know that his alternate self is still frozen somewhere in the Arctic and likely won't do anything to save him for the next seven decades.
As shown on a photo prime timeline old Peggy keeps by her side as she's bedridden in Captain America: The Winter Soldier, she had at least two children with her husband (who may or may not be SSR agent Daniel Sousa). With her alternate timeline self marrying prime timeline Steve, they won't exist in said timeline. She may have children with Steve, but those won't be the same.
The one thing that set the Endgame comeback in motion was the rat running along the exact buttons and switches needed to bring Scott back from the Quantum Realm. Couple this with the fact that Dr. Strange states that there was only one future timeline where they win, it's safe to assume there's countless timelines where the rat wasn't there, Scott is trapped forever in the Quantum Realm and the Snap remained in effect.
Imagine the thousands of timelines in which that rat got eaten by some random predator before it could get into the storage facility...
Captain America: Civil War If Zemo ever learned that not only the Avengers have reunited to save the world but now Tony Stark, the man whose weapons destroyed his country several times has been canonized to a saint for his noble sacrifice. Meanwhile his fellow Sokovians gain next to nothing except returning to a world where they are still without a country, and worst of all he is denied his death in the Snap by Thanos' hand. Without a doubt he is going to snap and likely become a threat again in Phase 4.
Of all the reinforcement Strange summons the Nova Corp is absent. Have the Nova Empire been conquered by the Kree post Snap after the destruction of Xandar?
The ending is sweet and all, but the elderly Steve Rogers will die in a few years (or months). The guy must be in his hundreds.
As mentioned in previous entries, bringing back all people to the post-snap world (a worldwide population growth of 100%, literally overnight, in a world that was already in the brink of collapse) will cause all sorts of problems, including famine and scarcity. But why did they do it this way? Why not simply roll everything back 5 years? Because, if they do so, Tony Stark would lose his family and daughter. Which is a good point, but it is also Protagonist-Centered Morality. "We don't trade lives... but some lives are more tradable than others".
That is assuming that, as we've speculated that Hulk can use the gauntlet so someone doesn't reform into a car that happens to be parked where they vanished, he didn't do something about that.
Also that there's a reason the Eye of Agamotto and the Time Stone is kept under heavy guard; from Doctor Strange's movie, it can only go back a few hours before it starts glitching, hence the Time Stands Still effect in the climax of that one. Combined with how longer-term time travel creates alternate universes, and it becomes a non-issue; certainly enough to raise an eyebrow, but Tony is still the person who says that and then immediately makes sure that time travel is possible.
Nat says that 50% of ALL life was killed. So imagine playing with your dog and it suddenly vanishes.
Also, imagine what the snap looked like to pets themselves. A dog could have just been playing with its owner, who is just suddenly GONE and they will have no understanding of why.
This is effectively the fourth time that Rhodey has been trapped in a small confined space and rendered helpless. The first and second times were in Iron Man 2 and 3, when the villains either took control of his suit, or locked him inside it. Then it happens in Civil War, where he falls out of the sky in "dead stick." Finally, in this morning he's trapped underground in the wreckage of Avengers HQ after Thanos bombs it with the rising water threatening to drown him. It's a miracle that the poor man hasn't developed claustrophobia at this rate.
Many people think Thor's behavior in the first half of this movie is just the result of the events in Infinity War. What they forget is that Thor: Ragnarok and Infinity War took place within days of each other. Meaning Thor was still fresh from losing his father, his hammer, his eye and his home. Following that, half of the Asgardian survivors are slaughtered by Thanos and his cronies, him losing Loki and then failing to kill Thanos when he should have and the snap occurring, resulting in half of all life in the universe getting wiped out. His life went from bad to worse in a matter of days, and it added to the toll of his guilt in addition to not killing Thanos when he had the chance to.