A year later, they'd slimmed down, found a new name and invented heavy metal. Few bands are so inextricably linked with a musical genre, but Sabbath set the template for everyone from Motörhead and AC/DC to Metallica and Guns 'n' Roses.

But the tune’s comparative catchiness makes the song the perfect gateway drug into the Surfers’ psychedelic noise, a sound nearly as influential in Eighties underground rock circles as Sabbath was to metal.

As tributes continue to pour in, two of Ozzy Osbourne's children — Jessica and Louis — have honored their late father in subtle ways after the former Black Sabbath frontman and legendary rocker died on Tuesday,