Slim was one of the foremost practitioners of the raw, gut-bucket, back alley blues associated with the postwar Chicago blues sound. He and his band, the Teardrops, were known as "the last real Chicago blues band" for their authentic, no-frills, straight-no-chaser performance of the music.
Slim's slash and burn guitar technique and booming vocals made for a commanding stage presence. His intense style was the blueprint that spawned much of the music played by modern blues artists and rockers. After catching one of Slim's electrifying live shows at a local nightclub Eddie Vetter invited Slim to open Pearl Jam's concert in Chicago. Magic Slim also had an encyclopedic repertoire of hundreds of blues songs in his head, giving his live shows a charming impromptu quality.