We lost Scarlett Johansson's character Natasha Romanoff (Black Widow) as she sacrificed herself to save Clint (Hawkeye). It was a win for feminism, but also super sad.
But the big shock death was that of Iron Man/Tony Stark (Robert Downey Jr). He sacrificed himself to save the universe at the very end of the film, using all the Infinity Stones to wish Thanos out of existence.
In the movie, the gang all have a funeral to wish him farewell, but the newly released deleted scene is really poignant and fans are devastated it wasn't used too.
It shows the seconds following the snap that killed Thanos and his army, after Pepper Potts kisses Tony's dead body. Everyone who fought alongside him kneels in a powerful tribute with inspirational instrumental music.
Directors Joe and Anthony Russo told USA Today they felt it didn't compliment the funeral scene at the end.
"It's a beautiful scene with moving performances, but we filmed it prior to Tony Stark's funeral. The funeral scene ultimately became a more resonant and emotional reflection on Tony's death for us."
We're not so sure they made the right call there. And people on social media aren't either.
Nonetheless, the movie was still amazing.
Earlier this month, Marvel Studios boss Kevin Feige announced at San Diego Comic-Con that Endgame had finally beat James Cameron's blockbuster to become the biggest movie ever.
He said Avengers: Endgame had grossed $US2.790 billion, dethroning Avatar's record of $US2.789 billion.
Fans flocked early to see Endgame when it was released in April, which meant its gargantuan box office was quite front-loaded. It only took Endgame five days to make it to $US1 billion, and 11 days to get to $US2 billion.
It overtook Titanic as the second biggest movie of all time after 12 days.
Endgame's record is based on box office receipts unadjusted for inflation. On that measure, Victor Fleming's 1939 Gone with the Wind takes the cake.