Believe it or not, this is our 100th mystery rock star yearbook photo! We've enlisted a true legend to mark this special occasion -- an artist who helped define hard rock and heavy metal through his work in several different famous groups.

Sadly, this singer, whose slight physical frame somehow contained one of rock's biggest voices, is no longer with us. But you can't listen to any halfway decent rock radio station for very long without hearing one of his anthems, and his favorite hand gesture has become nearly synonymous with the heavy metal genre.

OK, come on, you've got to know who we're talking about now, right? Click here to see if you're right or wrong, or shall we say, "evil or divine?"

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