Answer: quintessential metal song

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So, if someone asked me for the ideal song to listen to as an introduction to heavy metal, I would suggest this:

"Children of the Grave" from Black Sabbath's Master of Reality, 1971

I never tire of listening to that song. The rapid crunching of Tony Iommi's left-handed guitar work is metal as its archetypal best, and the song is wonderfully adaptable to different styles. White Zombie did a cover of "Children of the Grave," as did Racer X and several other bands, but my favorite version of it -- besides the different Iommi recordings -- is that done by Brad Gillis.

Gillis had come from the band Night Ranger to tour with Ozzy Osbourne, replacing the recently deceased Randy Rhoads. Ozzy released a live album of Black Sabbath songs from that tour called Speak of the Devil, and let me tell you, Gillis smokes on that album. It's hard to believe he came from -- and then went back to -- Night Ranger. His guitar work is fabulous on those Sabbath songs, and he turns in a wonderful performance of "Children of the Grave."

I think I will listen to it again, except this time I will select Rhoads's live version.

Cheers!

UPDATE:

Here's Tony Iommi:


Here's White Zombie's version:


And here's Brad Gillis: