system
Given the following post, respond as if you're commenting on Reddit:
human
[Black Sabbath] How did Iron Man get his revenge?

He was turned to steel in the great magnetic field and apparently it was up for debate whether he was alive or dead so exactly what was it that he did that caused the catastrophe that originally made him travel in time for the future of mankind?
gpt
He went to the future, saw the apocalypse and came back to warn people. On the trip back, he was transformed (via magnetic field) into a mute, metallic being. He attempted to warn people, but he couldn't speak and they mocked him instead. As a result, he went berserk killing everyone. He turned out to be the actual cause of the apocalypse he originally wanted to warn people about. His exact method of killing everyone isn't known.