Like Humble Pie, Thin Lizzy developed in rock 'n' roll's reverse: they went from tender jams to heavy grooves. But unlike Steve Marriott and the Pie, the Irish rockers never abandoned the singer-songwriter's mission. Phil Lynott was a poet, and he proves it on "The Rocker." Try burning out that chestnut, we dare you. But seriously, the Thin Lizzy of Jailbreak make their first appearances on 1973's Vagabonds. So does the band's twin guitar attack, which launched into some heady solos.