 Despite the waning popularity of shoot 'em ups, Hudson commissioned CAProduction to develop one as what would become the final Arcade Card game.CAProduction were working on a third entry in the "Thunder" trilogy following "Gate of Thunder" (1992) and "Lords of Thunder" (1993) when they were approached by Hudson.Concurrently, Hudson saw the popularity of the bishōjo adventure game series "Galaxy Fräulein Yuna" and saw potential at combining the two.