This game is about Whistle Knights that live in the Sky Fortress. After centuries of peace and isolation, the Sky Fortress has been found. You must help to defend it from your enemies with only your special bow. Buy and level up unique and devastating weapons, combine them and create your own custom powers. To shoot an arrow click inside the circle and drag to the opposite direction from your enemy and release to shoot your arrow. Each enemy has its weak parts like wings or propellers.