10 Characters Who May Kill Thanos In Avengers: Endgame
6. Iron Man
Tony Stark defeating Thanos could happen for two reasons. The first being that it'll be fitting, in terms of MCU canon. Iron Man was the first movie to enter the Marvel Cinematic Universe in 2008. It would make sense for the hero at the center of Marvel's first movie would defeat the franchise's greatest threat.
The other reason would be because it would make for a perfect ending to Tony's redemption arc. The man has been on a lot of characters sh*t list ever since he started a Civil War. A war which, let's remember, he wrapped a 14-year old kid named Peter Parker into. Now, that kid is dusted. To redeem his sins and to avenge the fallen (pun intended), there is no better way for Tony to do so than defeat Thanos.
Perfect motivations aside, let us not forget the tools that Stark has in his arsenal to drop the planet conqueror onto his derriere. His suit allows him to take Thanos airborne whereas Thanos himself can't fly. Tony can use that to his advantage, which he often did during the Avengers's first squabble with the purple giant. The advantage should still help the billionaire in a one-on-one rematch.