The "Avengers assemble" scene, also known as the portals scene, is the sequence leading to the climactic Battle of Earth in the superhero film Avengers: Endgame (2019), which sees the Avengers and their allies arrive on the battlefield through sling ring portals in preparation for a battle against the film's antagonist Thanos. It culminates with Steve Rogers / Captain America saying, "Avengers...assemble", the team's catchphrase and rallying cry in Marvel Comics. The scene features many cast members and characters who appeared in previous Marvel Cinematic Universe (MCU) installments, including several who had died in the preceding film Avengers: Infinity War (2018) during an event known as the Blip.
The catchphrase was not used in The Avengers (2012) because Marvel Studios president Kevin Feige felt it was not appropriate to include it, and the phrase was only half-uttered in Avengers: Age of Ultron (2015) because director Joss Whedon wanted to ensure that the film's scenes remained unaltered; this led to speculation from the audience if the MCU would ever use the line. The "Avengers assemble" sequence was not initially featured in the Endgame script, but was gradually integrated after the production team wanted to create a scene showcasing the return of the Blipped heroes ahead of the battle. Directors Anthony and Joe Russo settled on a quiet delivery of the line after considering a couple versions of the sequence. Weta Digital worked on visual effects for the scene while the musical piece that accompanies the scene, "Portals", was composed by Alan Silvestri. The scene received positive responses from critics and audiences.