So how long did Marvel know that Infinity War Part 2 was going to be titled Avengers: Endgame? Judging by the fact the title was named in the first teaser for Infinity War, a long time.
As pointed out on Reddit, the Infinity War teaser that was shown way back in 2014 at Marvel’s Phase 3 event, Robert Downey Jr and Tony Stark mention the “endgame” line from Avengers: Age of Ultron.
Here is the full line from Avengers 2: “Recall that? A hostile alien army came charging in through a hole in space…we’re standing 300 feet below it. We’re the Avengers. We can bust arms dealers all the live-long day, but…that up there? That’s the endgame. How were you guys planning on beating that?”
I also asked my source who told me Endgame was the title prior to the premiere of Infinity War how long he/ she knew the title for, and I was told for at least months before Infinity War.
As I previously said, Annihilation was never the title and that was all just a lie. It has always been Avengers: Endgame.
You’ll also note I said I was 100% certain that Avengers: Endgame is the title.
Here is the Infinity War teaser where Stark mentions it:
The movie gets released April 26, 2019 directed by Joe and Anthony Russo starring Robert Downey Jr., Chris Evans, Chris Hemsworth, Scarlett Johansson, Jeremy Renner, Karen Gillan, Paul Rudd, with Josh Brolin as Thanos.