How does a melodic death metal band accidentally create the sound for metalcore? Or how does the lack of a drummer help launch a genre that shaped the '90s? These pioneers didn't necessarily know the trails they were blazing, but they created entire subgenres of metal thanks to their ingenuity.

While Black Sabbath undoubtedly engineered multiple styles of metal, bands like Venom launched an entire genre that they didn't even play. Regardless of why these bands became the most influential of their respective generations, they all deserve credit for being musical mad scientists who changed music forever.

Black Sabbath – Master of Reality (Doom Metal)

You wouldn't be wrong to argue that "Black Sabbath" was the very first doom metal song, but when looking at Sabbath's early masterworks, it's Master of Reality that truly birthed generations of doom metal bands. Tony Iommi's thick and grimy tone mixed with the mid-tempo grooves of “Children of the Grave” or “Into the Void” is the primordial ooze for doom, and it's those dynamics that have been copied over and over for the last 50 years.

Metallica – Kill’ Em All (Thrash)

You've gotta give the credit to Dave Mustaine — he invented the sound we all call thrash. Kill ‘Em All showcased a lot of Metallica's NWOBHM influences on tracks like "Hit the Lights," but it's that Mustaine edge on "The Four Horsemen" and "Metal Militia" that made thrash what it is. Kill ‘Em All was the album that launched a thousand ships, helped make thrash the most popular metal subgenre in the world, and began the career of metal's most commercially successful band.

Venom – Black Metal (Black Metal)

Is Venom a black metal band? No. Is Black Metal even a black metal album? Nah. But it's the extremity of Venom's music at the time, plus the band's wicked image, Satanic lyrics and coining of the phrase "black metal" that ultimately kicked off metal's coldest subgenre. You may credit Bathory or Celtic Frost as the first pure black metal band, but Venom's influence was the direct launching point, and it deserves ultimate credit.

Possessed – Seven Churches (Death Metal)

No disrespect to Saint Chuck, but as the Death frontman often said, Possessed's Seven Churches is the first death metal album. The record has some thrash and black metal elements in there, but its raw technicality and punishing tone blended together with Jeff Becerra's vocal style is death metal as its most caveman-esque. *Headbangs in ooga booga*

Napalm Death – Scum (Grindcore)

From the filth-ridden pools of crust punk, powerviolence and extreme metal came a truly subversive form of music — grindcore. Napalm Death's Scum is a fairly undisputed pick for the album that set grindcore in motion, especially when it comes to provocative lyrics and the infamous micro-song. Every grind band has emulated "You Suffer" at some point in their career, along with the insane blast beats on tracks like “Instinct of Survival.” 

Godflesh – Godflesh EP (Industrial Metal)

Sure, most industrial metal acts sound more like Ministry than Godflesh, but the elements which make up Godflesh's 1988 EP really synthesized the genre. Godflesh basically took what Killing Joke did with their first album and made it uglier, darker and heavier, while the addition of a drum machine versus a human drummer gave the Godflesh EP its cold, mechanical feel. 

Korn – Korn (Nü-metal)

Everyone knows nü-metal came from Bakersfield. Korn essentially wanted to be a heavy funk band when they began jamming in the early '90s, but they accidentally invented one of the most polarizing genres in metal history. Korn's '90s discography was on its own level, though, and it all kicked off with their debut album and its opening track, "Blind." Massive down-tuned riffs, funky drums, rhythmic vocal lines and dark lyrics… nü-metal was perfectly synthesized on Korn's very first song.

Meshuggah – Destroy Erase Improve (Djent)

Okay, Periphery… djent is not a genre… but Destroy Erase Improve is essentially proof that Meshuggah are time travelers. Has any metal band ever been as forward-thinking and before-their-time? Hearing "Future Breed Machine" in the mid-1990s would've been like hearing Slayer in the 1960s, only this actually happened! It took an entire generation decades to catch up to the Swedish extremists, and now we've got djent-inspired butt rock on the radio.

At the Gates – Slaughter of the Soul (Metalcore)

Slaughter of the Soul is yet another case of influence over stylistic completion. How exactly can a melodic death metal album set off a chain reaction that creates metalcore? It's the riffs. Every. Damn. Metalcore. Band. copied Anders Bjorler and his guitar work, along with Adrian Erlandsson and his drumming. Even the guitar tone and the album's mix are complete examples of what metalcore would become. Death metal fans and metalcore fans agree… At the Gates' Slaughter of the Soul is flippin' awesome.

All Shall Perish – Hate, Malice, Revenge (Deathcore)

Deathcore was blasted into the metal underground by Job for a Cowboy’s Doom EP, but All Shall Perish’s Hate, Malice, Revenge predates the release by two full years. It’s perhaps the first example of a fully formed deathcore album, but since it was released on a small Japanese label in 2003, it didn’t really make the rounds until Nuclear Blast picked it up in 2005. This thing is gross in the best way.