Ryuki had two separate S.I.C. Hero Saga side stories published in Monthly Hobby Japan magazine. The first was titled Masked Rider Ryuki: Advent Calendar (MASKED RIDER RYUKI -アドベントカレンダー- Kamen Raidā Ryūki: Adobento Karendā^?) and featured original characters Kamen Rider Ouja Survive (仮面ライダー王蛇サバイブ Kamen Raidā Ōja Sabaibu^?) and his Mirror Monster the Genosurviver(ジェノサバイバー Jenosabaibā^?). The second S.I.C. Hero Saga story Masked Rider Ryuki: World of If (MASKED RIDER RYUKI -IFの世界- Kamen Raidā Ryūki: Ifu no Sekai^?) is an alternate telling that features Ouja Survive from Advent Calendar and also introducesKamen Rider Ryuga Survive (仮面ライダーリュウガサバイブ Kamen Raidā Ryūga Sabaibu^?). Advent Calendar ran from August to December 2004 and World of If ran from June to August 2005.