Here's fan-shot video of Twisted Sister drummer AJ Pero in what would sadly become his final performance, a tough cover of Black Sabbath's "Mob Rules."

Pero, who died on Friday (March 20) after reportedly suffering a heart attack, was appearing with Adrenaline Mob at Baltimore's Fish Head Cantina on the day before he died. Pero, 55, was a classic-era member of Twisted Sister who reunited with the group for an on-going stint in 1997. He'd also been appearing with Adrenaline Mob since 2013, a period that included the 2013 album Men of Honor.

Adrenaline Mob took to the stage last night (March 21) to pay tribute to their fallen friend, appearing with departed co-founder Mike Portnoy -- the drummer whom Pero replaced. “Tonight, we honor the passing of our beloved Adrenaline Mob brother AJ Pero by performing at Starland Ballroom in New Jersey," the band said, in a statement before the show. "AJ put his heart and soul into Adrenaline Mob, and would want nothing more than for the show to go on."

Portnoy also shared his condolences: “I am absolutely shocked and devastated to hear of the passing of my friend AJ Pero. He was truly a kind soul and a great guy. My deepest sympathies go out to my brothers in Adrenaline Mob and Twisted Sister for this terrible loss.”

Pero joined Twisted Sister in 1982, stabilizing the drummer's position ahead of their breakthrough hit Stay Hungry in 1984. He departed in 1987, following a tour supporting Come Out and Play, before returning a decade later.

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