The ending of Avengers: Infinity War shocked a lot of people since everyone's favorites were reduced to ash thanks to Thanos, who managed to fulfill his goal. As fans wonder how this will all be resolved in Avengers 4, some were rather surprised to see the Infinity Gauntlet broken and the damage it did to Thanos' arm. With the Avengers planning to make things better, fans are wondering how Thanos will be able to fight back, given the state of his arm.
During a special screening of Infinity War, The Russo Brothers hosted a Q and A where they answered various questions, one of which involved the fame done to Thanos's arm. The duo stated that the power it took to wipe out half of the universe was devastating, hence the price Thanos had to pay by taking the pain.
"His daughter is an emotional price, but the physical price is - you'll see it if you pause your DVD - right before he uses it to go back into the portal away from Thor while he's got the ax in his chest, his arm is burnt to a crisp. So the physical price is the extreme power that it took to enact his plan, he paid for physically, and when he sits down on the steps at the end of the movie you can see that it actually carries up into his neck and onto his face."
Considering how powerful the Infinity Stones are, this was a perfectly acceptable reaction and it does make the Mad Titan more vulnerable. While some of the leaked reports have suggested a new weapon for Thanos in Avengers 4, it's not yet clear if he will be able to wield it successfully. Expect the character to have a hard time taking on The Avengers during their rematch, especially with Captain Marvel by their side.
Avengers 4 comes out on May 3, 2019.