While Avengers: Endgame has the surviving heroes of the Marvel Cinematic Universe regrouping to undo Thanos' final victory, a different ending for Avengers: Infinity War may have changed who would participate in the heroes' desperate, new mission.

While promoting Endgame, Mark Ruffalo revealed that he had filmed an alternate ending to Infinity War that saw his character disintegrate with half of all life in the universe after Thanos' use of the fully- powered Infinity Gauntlet. And with at least two different endings filmed, Ruffalo wasn't sure if his character would survive the events of the film until he saw the finished movie for the first time.

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"I didn’t know until I saw the movie," Ruffalo admitted during a press junket interview with Yahoo!. "For one take, I did disappear, and then the other one I didn’t.”

Given the lengths Marvel Studios has taken to keep plot details under wraps in marketing its upcoming films, it makes sense that the studio would stage fake endings to keep the story secret. As Ruffalo has a history of accidentally spoiling MCU films, the actor was convinced he would die in Infinity War to avoid spoiling its sequel.

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"I was pretty sure it was gonna be me,” continued Ruffalo. "It’s like Survivor. It’s like, who’s gonna get kicked off the island? And I probably should’ve. … It’s like Project Runway for leakers.”

Directed by Anthony and Joe Russo, Avengers: Endgame stars Robert Downey Jr., Chris Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Jeremy Renner, Don Cheadle, Paul Rudd, Brie Larson, Karen Gillan, Danai Gurira, Benedict Wong, Jon Favreau and Bradley Cooper, with Gwyneth Paltrow and Josh Brolin. The film arrives April 26.