This game is shooting. Select a stage on the menu screen and defeat the emerging adversary with a arrow of an angel. When the angel 's HP becomes 0, the stage will be retried. If you defeat all enemies it will be completely clear and medals will be shown on stage selection. Depending on the stage items appear, and ability of an angel will be upgraded. However, upgrading is effective only after the stage you obtained. Operation is done with the keyboard or Xbox 360 controller. Save is done automatically in the stage clear.