The free-to-play games.
All math problems are addition. But this is done in a weird way. All you have to do is avoid clicking the correct answer . Simply click the incorrect answer in time to score. However, if the following correct answer is 9, then you must click the ⑨ . If you make one mistake or you take too long, the game is over. The tempo increases when level reaches 21, 41, 81, and 161. If the player reaches over level 100, a special message shows up on how to play Extra mode. Like Is That So?♪ , its not a requ