A German heavy metal outfit founded and fronted by powerhouse vocalist Udo Dirkschneider, U.D.O. emerged in the late '80s after Dirkschneider exited the popular power metal group Accept. Beginning with 1987's Animal House, Dirkschneider and a rotating cast of players carved out a huge swath of heavy metal real estate, averaging a full-length LP every year or so (2021's Game Over was the group's 17th full-length effort) and touring on the strength of an impressive catalog of European power metal that also included Accept classics like "Balls to the Wall" and "Fast as a Shark."