Morris performed as vocalist on Black Flag's earliest recordings, and his energized, manic stage presence was pivotal in the band earning a reputation in Southern California. Migdol was replaced by the enigmatic Colombian drummer Robo, whose numerous clicking metallic bracelets became part of his drum sound. The band played with a speed and ferocity that was all but unprecedented in rock music; critic Ira Robbins declared that "Black Flag was, for all intents and purposes, America's first hardcore band." Morris quit in 1979, citing, among other reasons, creative differences with Ginn, and his own "freaking out on cocaine and speed." Morris would subsequently form the Circle Jerks.