Serj Tankian worked with Chris Cornell on the music for The Promise, and the System Of A Down frontman recently spoke about his final interaction with the Soundgarden singer. At Germany’s Rock am Ring festival yesterday, Tankian joined Prophets Of Rage, the supergroup that includes Cornell’s Audioslave bandmates Tom Morello, Tim Commerford, and Brad Wilk along with members of Public Enemy and Cypress Hill, to sing Audioslave’s “Like A Stone” in tribute. Watch their performance below; previously, the surviving members of Audioslave shared footage of them playing an instrumental version of the song.