SEATTLE — A routine Foo Fighters show turned liturgical after Dave Grohl snapped his tibia during My Hero and refused to exit. He ordered, “Build me something worthy of rock and roll,” as roadies stacked four drum kits, six Marshall stacks, three bass cabs, and a Hammond into a towering throne. “Stonehenge with more reverb,” said livestreamer Jennifer Martinez. Grohl bled, barked orders, and fans started genuflecting. Rolling Stone dubbed the next 47 minutes the Sermon on the Mount of Amps. Eight feet up, Grohl conducted extended cuts and flung drumsticks like papal blessings. Tom Berkshire took one to the chest and swears his chronic back pain vanished. Dozens reported cures for tinnitus and lactose intolerance. “The Throne of Grohl is real,” Berkshire said. Others simply wept and bought merch. Copycats followed. Chad Kroeger dislocated his shoulder and played atop a Pyramid of Pain. A Portland punk band performed while vomiting into ceremonial buckets. Hospitals warned teens. Insurers added throne clauses. Grohl promised a permanent throne. “If they want an altar,” he said, “we’ll build a cathedral.”