2. Black Sabbath Vol. 4 (1972)

As groundbreaking and essential Black Sabbath are to heavy metal, their artwork, well, it wasn’t all that great. Except for Vol.4. This monochrome photo of Ozzy during of their gigs has “inspired” countless other metal covers, most notably, Sleep’s Volume Two EP and so forth. The original release on vinyl, features a gatefold sleeve with a page glued into the middle. Each band member is given their own photo page, with the band on-stage (and photographed from behind) at the very center.