Geezer Butler says he and his Black Sabbath bandmates felt a sense of shock when they watched Kiss for the initial time.

It was 1975 and Gene Simmons and business had been out opening for Sabbath on their U.S. tour. During a current conversation with Rock Cellar, Butler admitted his band was taken aback by the theatrics of their opener.

“Kiss was the first band that ever used stage production,” the bassist explained. “Up until Kiss came, bands like Black Sabbath used to just go on and plug in and play. Kiss was the first one to use pyro. You’ve never seen that. I mean, the shock of that. And they were supporting us, so they weren’t even headlining.”

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Butler additional noted what it was like to see Kiss’ fiery antics.

“I went out and watched them. There were all these flames coming out the stage and everything,” he recalled. “It was like, ‘Oh, my God, what’s going on here?’”

‘What the Hell Just Happened?’

While fans had been undoubtedly impressed by Kiss’ stage production, Black Sabbath couldn’t aid but really feel outshined.

“It was tough to follow them,” Butler confessed. “We went on just as an ordinary band, no effects or anything, and everybody else still had their mouths wide open from seeing Kiss. We were like, ‘What the hell just happened?’”

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“It was impossible to follow Kiss after the production,” Butler continued. “When I watched them play, I didn’t even listen to the music. I was just astounded by the stage production.”

According to Butler, Kiss’ influence pushed concerts in “a completely new direction,” as “people had to start thinking about stage production.” He and Black Sabbath also discovered a precious lesson: “We made sure that we never had Kiss supporting us again.”