WARNING: The following article contains major spoilers for Avengers: Endgame, in theaters now.
As expected, Avengers: Endgame brings back the heroes, and the half of the universe, than Thanos snapped away in 2018's Infinity War. The Decimation is undone after the surviving Avengers and their allies gather the Infinity Stones from the past. However, to ensure the Mad Titan can't enact his plan again, the heroes unite to defeat his forces in the most rousing battle the Marvel Cinematic Universe has ever seen.
But such a victory comes at a price, and sacrifices have to be made. As a result, not everyone -- whether hero or villain -- make it out of the blockbuster sequel alive.
BLACK WIDOW (PRESENT-DAY)
In 2024, the Avengers come up with the "time heist" to collect the Infinity Stones from the past, with Clint Barton and Natasha Romanoff sent to distant Vormir to claim the Soul Stone. After dropping off Nebula and War Machine on Morag, from Guardians of the Galaxy, in 2014 to get the Power Stone, they continue on in pursuit of the Soul Stone, unaware of the toll required.
There, the Stonekeeper (aka the Red Skull) informs them the cost is a life, and after a scuffle to see who draws the short straw, both Avengers tumble off the cliff where Gamora perished in Infinity War. However, Black Widow slyly tethers Clint to the rocky edge, and as he tries to cling to her, she sacrifices herself. Played by Scarlett Johansson, this was Black Widow's eighth MCU appearance since debuting in 2010's Iron Man 2.
NEBULA (FROM 2014)
The Avengers' heist develops a major flaw when the evil Nebula (Karen Gillan) in 2014 accesses the redeemed Nebula's memories as the latter arrives on Morag. When 2014's Thanos deduces the "time heist," past Nebula eventually replaces her future counterpart and infiltrates the Avengers to bring Thanos' legion to 2024. There, 2014-Nebula, desperately aiming for her father's approval, tries to steal the Infinity Stones for the Mad Titan.
That leads to showdown between 2014-Nebula, the future Nebula and the past Gamora, who realizes she can't let the Stones fall into Thanos' hands again. Future Nebula kills 2014-Nebula, which permits Clint to escape with the Stones. 2024's Nebula survives the finale, and officially joins the Guardians of the Galaxy, so we'll be seeing her around.
THANOS' GALACTIC MILITARY (FROM 2014)
Knowing Earth's Mightiest Heroes are packing numbers, past Thanos makes sure the military he brings to 2024 is as strong as ever, with the Black Order, the Outriders and a legion of Chitauri and their Leviathans. Their job is to secure Tony Stark's (Robert Downey Jr.) tech-based Gauntlet for Thanos to use this time to snap all life out of existence. But when Iron Man steals the Stones back from the Mad Titan, he performs his own snap and turns Thanos' forces to dust.
Ebony Maw, Proxima Midnight and everyone else under Thanos' commands feels what the victims of Infinity War's Decimation experienced, with their ashes scattering to the winds.
THANOS (FROM 2014 & 2019)
Thanos (Josh Brolin) is first killed in 2019, when the Avengers, mere months after Infinity War's climax, locate his space retreat, the Garden. Tipped off by an energy surge, they track him down, with Captain Marvel, Bruce Banner (in his Hulkbuster armor) and War Machine restraining the tyrant for interrogation. However, they realize the surge was caused by the destruction of the Infinity Stones, which leads an enraged Thor to decapitate Thanos using Stormbreaker, finally "going for the head."
Thanos is killed a second time, as the 2014 version who travels to 2024 also perishes in Tony Stark's snap. Seeing his forces wither away, he simply takes a seat on the debris outside the destroyed New Avengers compound, resigned to his fate.
IRON MAN (PRESENT-DAY)
When Thanos pompously mocks Tony with his "I am inevitable" comment, the hero simply replies with "I am Iron Man!" before his moment of glory. Tony performs his snap and the gamma radiation that courses through his body mortally wounds him. In his final moments, he's comforted by Spider-Man, who tears up at losing his mentor once again.
The soul-crushing last words come when Pepper Potts (Gwyneth Paltrow) consoles him until he draws his final breath. She tells him he can finally rest, having achieved his Age of Ultron vision of "peace in our time," and plants a kiss on his cheek. Tony doesn't utter a word, but his silence speaks volumes. This was Downey's 10th appearance in the MCU since Iron Man, truly marking the end of an era.
Directed by Joe and Anthony Russo, Avengers: Endgame stars Robert Downey Jr. as Iron Man, Chris Evans as Captain America, Mark Ruffalo as Bruce Banner, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow, Jeremy Renner as Hawkeye, Brie Larson as Captain Marvel, Paul Rudd as Ant-Man, Don Cheadle as War Machine, Karen Gillan as Nebula, Danai Gurira as Okoye and Bradley Cooper as Rocket, with Gwyneth Paltrow Pepper Potts, Jon Favreau as Happy Hogan, Benedict Wong as Wong, Tessa Thompson as Valkyrie and Josh Brolin as Thanos.