"XZR: Idols of Apostate"), the first game in the series, was originally released for the NEC PC-8801 on July 1988.[2] It was subsequently released for the MSX2 and NEC PC-9801 on August and for the X1 turbo on September.[3] The gameplay included action-platform elements,[4] switching between an overhead perspective and side-scrolling sections.[1] The plot of the original XZR has been compared to the later Assassin's Creed video game series.[5] The soundtrack for the PC-8801 version was composed by Yujiroh, Shinobu Ogawa and Tenpei Sato.[6]