Okay, we get it. You like Sabbath. Everyone does. But out there is a whole big world of '70s metal bands beyond Sabbath -- even beyond Sir Lord Baltimore, if you can believe that. The '70s offered so much in the way of doom-and-gloom heaviness that it's criminal so many stop with Ozzy, Tony, Geezer, and that other guy. If you're out of high school and still think Vol. 4 is the pinnacle of human heavy metal achievement, it's time to get with the program.
See also: The 20 Greatest Metal Albums in History