Black Sabbath — heavy metal's founding fathers, purveyors of the almighty riff and universal influencers of all heaviness thereafter — stand as one of the most important figures in all of recorded music and this notion is not lost half a century after the release of their first album. In celebration of the Ozzy Osbourne era of the group, we've ranked every song from worst to best.

There's quite the dividing line in this era of Sabbath's extensive catalog. The band's first six records — Black Sabbath (1970), Paranoid (1970), Master of Reality (1971), Vol. 4 (1972), Sabbath Bloody Sabbath (1973) and Sabotage (1975) — represent, arguably, the greatest album streak in metal's history.

It quickly fell apart from there, however, as drug abuse rattled the band's creativity and interpersonal relationships. Technical Ecstasy (1976) and Never Say Die! (1978) had fleeting bright moments, but were mostly marred by outlandish stylistic heaves of desperation that had no business being touted as music made by Black Sabbath.

Ultimately, those two records broke the band and necessitated the firing of Ozzy Osbourne, who was spiraling further out of control than any other member of the group.

There was a brief reunion of the original lineup in 1985 for a Live Aid benefit gig and it wasn't until 1997 that they'd all be onstage once more, this time for quite a longer spell. Attempts were made to write new music with Ozzy during this time, but only resulted in two singles — "Psycho Man" and "Selling My Soul" — while another new track, "Scary Dreams," was resigned strictly to live performances and never officially released.

After these writing sessions never amounted to a full length album, most had abandoned hope that the Sabbath would make another record with Ozzy, leaving the lowly Never Say Die! as a sad and sorry reminder of what once was.

READ MORE: Top 25 Doom Metal Albums of All Time

Instead, the principal members of Sabbath — Tony Iommi and Geezer Butler — got back with Ronnie James Dio and brought drummer Vinny Appice into the fold for a reunion under the banner Heaven & Hell, cutting one album before Dio's untimely death in 2010.

This paved the way for another reunion, this time with Ozzy while Sabbath and estranged drummer Bill Ward duked it out in the press over his status within the band. Cut to 2013 and 13, the first Black Sabbath album with the Prince of Darkness back at the helm, was released, though with Rage Against the Machine drummer Brad Wilk behind the kit.

The Rick Rubin-produced album had a very specific aim — to recapture the morbid blues vibe the band had channeled on their groundbreaking debut. As you'll see in this list below, we weren't bashful in addressing this pigeonholed ideal for the long-awaited comeback.

Now, onto what you came here for! Scroll through the gallery below to see how we ranked the Ozzy era Black Sabbath songs.

Black Sabbath Songs Ranked Worst to Best (Ozzy Osbourne Era)

Head here to listen to and follow Loudwire's 'Ultimate Doom Metal' playlist, featuring Black Sabbath and a lot more.

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