Iron Man (song)
"Iron Man" appears to be about a man who travels to the future and witnesses the Apocalypse. On his way back, he is caught in Earth's magnetic field, and turned to steel. When he comes back, he tries to warn the people about the Apocalypse, but they do not believe him, and shun him, so he takes his revenge by killing them all, thus bringing about the Apocalypse he saw. It would appear that he died and came back to life, for "vengeance from the grave kills the people he once saved" is a line from the song.
"Iron Man" has been used many times, and is frequently performed at events. Its riff has become one of the most easily recognizable riffs in music.
The 2008 movie Iron Man features portions of this song at the end of the movie.