A stark contrast. Driven by Bill Ward’s frantic, jazz-tinged hi-hat and Ozzy’s harmonica (a nod to their blues roots), “The Wizard” is a folk-metal hybrid about a mystical figure who brings joy. It proves the band wasn’t one-dimensional. The harmonica and guitar duel in a hypnotic, stoner-rock groove that predates bands like Kyuss by 20 years.

Named after an H.P. Lovecraft story, this song is pure proto-thrash at its core. It speeds up, driven by Ward’s manic drumming and Iommi’s power-chord attack. The lyrics tell of a dreamer whose soul becomes a star. It’s chaotic, messy, and glorious.

On a damp autumn day in 1969, four working-class lads from Aston, Birmingham, walked into Trident Studios in London’s West End. They were exhausted, having played countless gigs in German clubs and English dives. They had been booked for a quick, live-in-the-studio session to capitalize on the minor buzz surrounding their new, darker sound. They were given a meager budget and just 12 hours of studio time. No one—not the band, not the label, not the engineers—realized they were about to forge the blueprint for an entire musical genre: heavy metal.

The original 1970 UK vinyl mix (Warner Bros. WS 1871) or the 2014 “Sanctuary” reissue. Avoid early 2000s “remasters” which compress the dynamic range. The raw, roomy sound is essential to the experience.

Black Sabbath, originally a blues-rock band called Earth, was losing gigs to louder, flashier acts. In a moment of desperation, guitarist Tony Iommi, vocalist Ozzy Osbourne, bassist Geezer Butler, and drummer Bill Ward decided to pivot. Butler, obsessed with the occult and the writings of Dennis Wheatley, noticed people in the audience actually liked it when the band played a dark, bluesy number called “Black Sabbath.” The band leaned into the fear, the dread, and the industrial gloom of their Birmingham surroundings—a city still scarred by WWII bombings and choking on factory smog. The album was recorded in a single day (October 16, 1969) for around £1,800 (approximately $4,000 today). Engineer Tom Allom and producer Rodger Bain captured the band playing live, with very few overdubs. The result is raw, unpolished, and possessed of a strange, cavernous reverb—largely because Trident’s studio floor was made of wood, and the drums were placed on risers that picked up every vibration.

On Friday the 13th, 1970, a bell tolled. A riff descended. And heavy metal was born. The world has been a little heavier—and a lot more interesting—ever since.

In 2015, the US Library of Congress selected Black Sabbath for preservation in the National Recording Registry, deeming it “culturally, historically, or aesthetically significant.” The album that critics once called a “sad joke” now sits alongside the works of Beethoven and Louis Armstrong.