27| Tony Stark

Thanos. Oh, he who instilled fear in countless human beings, died for a teenager and some glittering gems.
Peter Parker, the teenager who managed to kill him thanks to the gauntlet and his ability to do so despite knowing it was dangerous. Just a vigilante and hero under 20, with little experience in that kind of fighting.
I wasn't really planning on Peter being the one to use the gauntlet; it was because it was the only way they could win. There were so many possibilities, and only one where he would have to use the gauntlet would guarantee victory.
There were other destinations, several where Peter put on the gauntlet but they failed to win
Dr. Strange didn't want to mention to Tony what he would actually have to go through to reach the only destination where they could win; he knew that, being the stubborn man he is, he would look for another way to keep the kid from having to use the gauntlet.
After Thanos died, Peter was left extremely weak and it seemed he wouldn't survive. Many thought he might die right there, but he was actually surviving, even though it wasn't visible. Dr. Strange didn't mention that he would survive, but Tony, even knowing Peter had little chance of living, clung to him, hoping he would stay conscious, and that's what kept him alive.
His body was left almost without energy, the right side of his torso and above were covered in burns, the hand he used to wield the gauntlet was unresponsive, and parts of the right side of his suit were destroyed.

(Eres Peter and allavia follow where they are fighting against Thanos)

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