See Serj Tankian, Prophets of Rage Team for Chris Cornell Tribute

System of a Down singer and Audioslave members perform "Like a Stone" at Germany's Rock im Park Festival

Serj Tankian performed alongside Prophets of Rage at a German fest to pay tribute to Chris Cornell with a cover of Audioslave's "Like a Stone."

Update: Prophets of Rage performed Audioslave hit "Like A Stone" in Berlin last night without a lead singer. Instead, the band held a spotlight at an empty microphone stand onstage while rendering an instrumental version of the song. Rage/Audioslave guitarist Tom Morello tweeted about the audience's "beautiful" participation. 

Earlier, System of a Down's Serj Tankian made a surprise appearance during Prophets of Rage's set at Germany's Rock im Park Festival to pay tribute to Chris Cornell with a cover of Audioslave's "Like a Stone."

Both System of a Down and Prophets of Rage – which features Cornell's Audioslave band mates Tom Morello, Brad Wilk and Tim Commerford – were on the lineup for the Nuremberg, Germany fest. Earlier in the week, Prophets of Rage posted a video of them rehearsing the Audioslave cut, Loudwire notes.

Cornell last sang "Like a Stone" in January during a one-off Audioslave reunion at an anti-Trump benefit concert, the band's first performance together in nearly 12 years.

"It's unbelievable," Morello told Rolling Stone of Cornell's death. "I don't know what the phases of mourning are, but I'm in the first one. I still expect this to be some kind of mistake."

Tankian, who collaborated on music for the film The Promise with the Soundgarden singer, also spoke to Rolling Stone about his last two encounters with his friend.

"We had this long chat, sitting next to each other," Tankian said, adding that he and Cornell discussed working on more films. As Cornell told Tankian, "'I'm really excited. I'm doing this tour with Soundgarden. I've got these other ideas.' He had plans, man."

Tankian added that Cornell was "one of those guys" that "tried to make everyone in the room feel comfortable with themselves. He was generous that way, with his emotions and time."