<Table> <Tr> <Td> "Children of the Grave" (1971) </Td> <Td> "Iron Man" (1971) </Td> <Td> "Tomorrow's Dream" (1972) </Td> </Tr> </Table> <Tr> <Td> "Children of the Grave" (1971) </Td> <Td> "Iron Man" (1971) </Td> <Td> "Tomorrow's Dream" (1972) </Td> </Tr> <P> "Iron Man" is a song by British heavy metal band Black Sabbath . It is taken from their second studio album, Paranoid, released in 1970 . It was later included on their initial greatest hits compilation We Sold Our Soul for Rock' n' Roll (1976), as well as all subsequent greatest hits compilations; The single version was included on the Greatest Hits 1970--1978 album . </P> <P> Upon hearing the main guitar riff for the first time, vocalist Ozzy Osbourne remarked that it sounded "like a big iron bloke walking about". The title became "Iron Man", with Geezer Butler writing the lyrics around the title . Ozzy Osbourne sang behind a metal fan to get the sound effect in its first line,' I am Iron Man!' . Despite this, the song has no connection to the Marvel Comics character of the same name . </P>

Who sings the song i am iron man