Avengers: Infinity War - 14 Things You Probably Didn't Notice

2. Thanos' Injuries

It may have gone unnoticed the first time, but if you watch the finale a few times, you can see the cost of the snap to Thanos. Not only does it cost him "everything" as he mentions to Gamora, but the use of the Stones partly destroys the Gauntlet (though it still works as he uses it to escape) and leaves Thanos himself scarred pretty badly in the aftermath.

His arm is visibly charred as if the Stones have burnt him, and there's clearly a suggestion that it's not only the Gauntlet but also the wearer that needed to be up to the powers of the combined Stones to ensure the snap actually worked.

It could be that those injuries are going to be key, too if someone else is to use the Gauntlet to undo his snap in the end. Because that person would have to be able to withstand some serious damage. There are definitely possibilities to that end already, as Captain America remains alive - and it would fit that he would make that sort of sacrifice - and Thor has already foreshadowed the fact that he is capable of wielding weapons of unimaginable power that normal people simply couldn't cope with. That sounds like the kind of line that leads somewhere important.