If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
In this game there will be a grid of randomly placed blank squares, a series of squares connected horizontally or vertically form a group, before each group is a block with a number on it. The object of this game is to fill in the squares with numbers from 1 to 9 so that the numbers in the groups do not repeat and that the numbers sum up to the number before the group. The faster you finish the game, the higher your score. When you are stuck, you can click the hint button to get some hints, but you will suffer a time penalty.
This game is played by mouse only.