You control a circle with a number on it. Other circles with different numbers on them enter the screen and keep moving in it for a few seconds. You need to move and gather the ones with lower number than yours to earn score and meanwhile, avoid hitting other circles because you will lose if you do so. Also note that whenever you eat another circle, your number changes. So you need to always keep an eye on your number to decide what to do next. The number of circles and their moving speed will increase as you progress and so it becomes more difficult the further you go