Founding Slayer guitarist Jeff Hanneman stepped onstage with his band at this past Saturday’s Big 4 concert in Indio, CA, marking the first time he has played with Slayer since last October. In January, Hanneman contracted necrotizing fasciitis, likely caused by a spider bite, and has been undergoing surgeries, skin grafts and intense rehab since. Hanneman surprised the crowd of 50,000 when he walked out onto the stage, unannounced, and played the two-song encore, “South of Heaven” and “Angel of Death.”

Backstage in Slayer’s dressing room afterwards, Hanneman relaxed on a couch and said, “I’m the happiest man in the world.”

Gary Holt, guitarist for Exodus, has been the primary guest guitarist with Slayer since the band started its 2011 touring schedule in February, and will continue in that capacity until Hanneman has completely recovered.