Avengers: Endgame co-director, Anthony Russo had spoken to Watching Hollywood, and they had also put out a post which said that the “I love you 3,000” that line had been one of the many contributions made by the actor, Robert Downey Jr. Anthony Russo had said that RDJ told them a story of how one of his children would tell him, “I love you 3,000”, and this ended up being in the movie.
Another interesting story was the one about the iconic line, “I am Iron Man”. Tony’s big comeback at the Mad Titan had been added at the very last moment and was not planned from the beginning. This is what Joe Russo said:
“Tony used to not say anything in that moment. And we were in the editing room going, ‘He has to say something. This a character who has lived and died by quips.’ And we just couldn’t; we tried a million different last lines. Thanos was saying ‘I am inevitable.’ And our editor Jeff Ford, who’s been with us all four movies and is an amazing storyteller, said ‘Why don’t we just go full circle with it and say I am Iron Man.’ And we’re like, ‘Get the cameras! We have to shoot this tomorrow.’”
Directed by Joe & Anthony Russo, Avengers: Endgame stars Robert Downey Jr., Chris Hemsworth, Mark Ruffalo, Chris Evans, Scarlett Johansson, Benedict Cumberbatch, Jeremy Renner, Don Cheadle, Tom Holland, Chadwick Boseman, Paul Bettany, Tom Hiddleston, Idris Elba, DanaiGurira, Peter Dinklage, Benedict Wong, Elizabeth Olsen, Anthony Mackie, Sebastian Stan, Gwyneth Paltrow, Josh Brolin, PomKlementieff, Karen Gillan, Dave Bautista, Zoe Saldana, Vin Diesel, Bradley Cooper, Chris Pratt, Paul Rudd, Samuel L. Jackson, CobieSmulders, Tessa Thompson, Evangeline Lilly, Michelle Pfeiffer, Michael Douglas, TildaSwinton, Ty Simpkins, Ava Russo and Brie Larson.