In 1993, Tool and Rage Against the Machine were both fast-rising forces in the world of alternative rock and metal. Their histories were already intertwined. The two groups' respective guitarists, Adam Jones and Tom Morello, grew up together and even played together in a band in high school. Years later, Tool's singer, Maynard James Keenan, would provide guest vocals on "Know Your Enemy" off RATM's groundbreaking 1992 debut. However, it was a different song — a Tool original — that Keenan and his bandmates played when they invited Rage's hyperkinetic MC Zack de la Rocha onstage with them at Lollapalooza in July 1993 (the same Lollapalooza, by the way, where RATM infamously stood onstage naked to protest music censorship). Just a few months before, Tool had released their own debut album, Sober, which featured guest spoken-word courtesy of Henry Rollins, on the standout cut "Bottom." De la Rocha took Rollins' spot at Lollapalooza, but contributed his own original spoken-word part, delivered in a slow-burning whisper, building toward the song's incendiary climax.
As seen in the nostalgic, VHS-quality video above, once the song erupts, de la Rocha and Keenan take turns whipping around the stage, shirtless and full of youthful exuberance and aggression. By the performance's end, the crowd are in a frenzy, too, surfing and moshing, trying to match the energy level of their heroes onstage. The video doesn't include the full song, cutting in only at the start of de la Rocha's cameo, so find a full audio stream below to hear it in all its electric, early-Nineties glory.