Tony Stark "I am Iron Man"
Sitting on the throne and ruling Stark Industries, while enjoying the perks of the rich life, but there was a personality change that saw him save the entire universe, which cost him his life.
When did Tony Starks's life take a change in the Marvel Cinematic Universe?
The change came around when Spiderman entered the scene we saw the shift from playboy to father figure take place. He took Peter Parker under his wing and molded to be a better version of himself.
In Avengers Infinity War it was visibly that Tony was out to protect Peter Parker and unfortunately at the end, Thanos snapped his fingers taking away half the universe.
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In Avengers Endgame, We saw Tony start his family and have a daughter, who could forget the line "I love you 3000". Tony sacrificed his life ensure everyone around him to be safe,
This has to be one of the best story arcs. We saw him go from Playboy and his team not knowing if he could make the ultimate sacrifice. EndGame proved Tony will sacrifice everything for the safety of everyone.