Jeff Hanneman, who passed away last week at the age of 49, was never the face of Slayer, the seminal metal band he co-founded with Kerry King in 1981. King was the more outspoken of the pair, and his look — giant beard, shorn head, tribal tattoos — made him a focal point. Dave Lombardo, the band’s original drummer, defined metal drumming with his merciless double-bass attack, often needing someone to push him back on his stool when he inevitably wore himself out. As for Tom Araya, the Chilean-born bassist and vocalist — well, they don’t call those guys “frontmen” for nothing. Hanneman? He was the other guitarist, a burly blond guy with a penchant for Raiders jerseys and the look of a former pro wrestler gone to seed.

But if Slayer had a soul (and how the long-dead PMRC would wince at that) it was Hanneman. He wrote their best-loved songs (including both “Raining Blood” and “Angel of Death”) and drove the lyrical direction away from their initial ambiguous focus on “evil” towards real horrors, namely war. And it was his guitar sound — and the blazing fast solos he volleyed back and forth with King — that established Slayer as something more than just another metal band. Reign In Blood, a relentlessly punishing 29-minute long LP released on October 7, 1986, still stands as the pinnacle of speed metal. I bought it the day it came out — on cassette, duh — and was initially confused by two things: The Def Jam imprint, and the fact that the program repeated on both sides. Then I put it in my Walkman (probably replacing Metallica’s Master of Puppets), and there it stayed, autoreversing again and again and again. This was everything that had come before refined to a razor-sharp edge. It was hard to believe any single album could ever be heavier or faster or more brutal. Even the title was perfect.

From that concentrated point, this malignant tumor on the vitals of music, Slayer metastasized. Rick Rubin, who produced Reign In Blood, was producing the Beastie Boys’ Licensed To Ill at the same time, and he enlisted King to play guitar on both “No Sleep ‘Til Brooklyn” and “Fight For Your Right (To Party).” And Public Enemy, who were in the process of distilling hip-hop to its essence in much the same way Slayer did metal, sampled Hanneman’s crushing breakdown riff from “Angel of Death” for the equally powerful “She Watch Channel Zero?!” Power recognize power. And groove recognize groove—while they weren’t exactly the J.B.s, Slayer’s four-piece assault was as precise as it was fast.

This became only more evident when you saw them live: It was like standing on the sidelines of an NFL game instead of watching on TV. Or if you were brave enough to wade into the pit, like playing in one. It was stronger, faster, bigger and far more dangerous, an hour-long adrenaline rush that left participants and observers bleeding. I watched one show from the crumbling balcony of New York’s Roseland theater, as concrete dust and flakes fell onto my head and the crowd worked itself into a whirling frenzy below. This was in 2002 and they were still playing songs from the early ‘80s, only with a surgical precision that was absent from their earliest recordings. For many of Slayer’s earliest fans, they were the only metal band that mattered. And, at that point, with “nu-metal” rising and Metallica becoming some kind of monster, maybe they were right.

It’s hard to imagine Slayer without Hanneman, even though the band has soldiered on without him on and off since 2011, when he first came down with the necrotizing fasciitis (a Slayer-sounding disease if there ever was one) that may have eventually led to his death. But those were tours, where fill-ins Gary Holt (Exodus) and Pat O’Brien (Cannibal Corpse) simply needed to play Hanneman’s familiar riffs. It’s something else entirely to expect someone else to be able to step into Hanneman’s role as creator and songwriter (although Araya has involved himself more and more in the process over the years). If Slayer does continue, if they record an 11th studio album, it will be readily apparent that something essential is missing. And maybe Hanneman will finally get his just due. Too bad it will come too late.