Endgame would play out as an adaptation of the comics. That film's final battle was still a visual treat, especially the Avengers assemble portals scene. Avengers: Endgame's creative team fought over two versions of the film's portals scene.

The portals scene was reworked in post-production (along with, famously, Robert Downey Jr'.s 'I Am Iron Man' one-liner) and the rest is history – even if Endgame writer Stephen McFeely freely admitted, "I thought the first cut worked pretty well."

Avengers: Endgame saw Hulk putting on the Infinity gauntlet and snapping the blipped characters back to life. But unless the actual moment, nobody was sure how their return would be shown onscreen. Directors Joe and Anthony Russo claimed the portals scene underwent a lot of changes in the post production.

Avengers: Endgame ’s “Portals” scene is one of the most iconic moments in the Marvel Cinematic Universe. The emotional weight of all those Marvel heroes joining the final battle against Thanos had audiences jumping out of their sets and cheering.

There was probably some debate regarding the most famous moment, I think, of all the Marvel films, which is the portals opening at the end of Avengers: Endgame. The original concept was that the camera rotated around Steve Rogers and everybody was collected behind him.

From Black Widow’s sacrifice on Vormir to Tony Stark’s heartfelt "I love you 3000" phrase and Steve Rogers' emotional ending, every scene packed an emotional punch. But perhaps none were as iconic as the return of the Infinity War casualties.