東方神妙災　～ Autocatalysis of Unrecognizable Katzenjammer is a fan-made Touhou scene game, following the style of games such as 弾幕アマノジャク　～ Impossible Spell Card or Spell Card Collection, where you fight through a multitude of spell cards declared by a multitude of bosses playing as Sanae, utilizing (or not) miraculous items or gadgets to help you on these battles. The game contains original art and music compositions (alongside some borrowed tracks), as well as new, original characters.