 In contrast, the original John Lee Hooker blues hit "Boom Boom" was recreated in the style of Schlager, a simple, sanitized popular German musical genre that emerged after World War II, in part as a backlash against American rock'n'roll.The three cover songs were used in trailers for .Seven original songs were written for the label, each inspired by a different genre of 1960s pop music, but with lyrics that reflected the Wolfenstein universe.