Mark Ruffalo has said that Hulk/Bruce Banner’s has a specific arc that’s playing out across Thor: Ragnarok, Avengers: Infinity War and Avengers: Endgame, and the idea is that together the story will feel like a standalone movie for the character (who hasn’t been gifted with a solo movie since The Incredible Hulk in 2008).
Thanks to Thor: Ragnarok, we know that Hulk had been spending the last few years killing it in the gladiator ring on Sakaar, but because of events during the opening of Avengers Infinity War he found himself back on Earth to help try and pummel Thanos and his minions.
Could we finally see Banner and Hulk melding into one super-strong, highly intelligent individual a.k.a.
Avengers: Endgame will also be the culmination of the “huge change” Hulk will go through starting in Thor: Ragnarok, meaning that we will likely see a lot more cooperation between Bruce and Hulk by the time the film is over.