You play as a spirit called “Aeriid” that oversees the balance between good and evil. Aeriid can switch between two phases, Aero (good) and Siid (evil), to control the powers of good and evil by hitting them with “spirit orbs” of the opposite type.

Eliminate angelic sprites to give more power to the evil side, and demonic sprites to give more power to the good side. Keeping them balanced allows you to get a large amount of score, while giving too much power to either side will cause a Chaotic Being of that type to appear.

Chaotic Beings are gigantic monsters formed from excess power, and are the embodiment of spiritual chaos. Hitting a chaotic being with the opposite type of spirit orbs will cause the balance to gradually return. Once perfect balance is reached, the Chaotic Being dissipates (and you get lots of score).