Control the ball to acquire the items on the map and avoid obstacles. Gameplay seems to be very simple. But as more obstacles appear and the two bars on the left and right grow shorter and disappear ultimately, the word ¡®Change¡¯ shows up and some changes occur in the gameplay such as reversed control or slower ball. That¡¯s when you have to watch out because the ball will go ¡®Boom¡¯ unless you don¡¯t get used to such changes.