Saturday was Green Day’s first time ever playing Outside Lands, and the loud, high-energy band was perfectly suited for the festival’s massive Polo Field, waking up a crowd that had taken a nap during Mac DeMarco’s sweet but sleepy performance earlier in the day.

“Who knows how to play guitar?” Armstrong called out to the crowd. “It’s only three f—king chords.”

And then Montgomery, aka Monty, went on stage, and KILLED it!