Ancient Corp. isn't well known besides being managed by Yuzo Koshiro, but they've developed games for other companies such as Sonic the Hedgehog (Game Gear and Master System), Streets of Rage 2, ActRaiser 2, Robotrek, Beyond Oasis, The Legend of Oasis, Vatlva, Shenmue, Car Battler Joe and Amazing Island. However, Protect Me Knight was Ancient's first original game and self-published series.