By 1978, Styx had grown from strident prog to theatrical rock (“Lords of the Ring”) laced with pop melodies. They'd also developed a split personality, spanning the whimsical folk-pop of “Sing for the Day” and the Deep Purple–ish heavy rock of “Blue Collar Man (Long Nights).” James Young’s impassioned howls (“Great White Hope”) are complemented by Dennis DeYoung’s mellow balladry (“I’m O.K.”) and Tommy Shaw’s grizzled soul (“Renegade”). The band’s triumphant peaks, however, are their huge unison choruses, such as on “Pieces of Eight.”