!!! Very simple and funny game !!!
The game starts with a board with three balls chosen out of some different colours. You can move one ball per turn, and you may only move a ball to a particular place if there is a path (linked set of vertical and horizontal empty cells) between the current position of the ball and the desired destination. The goal is to remove balls by forming lines (horizontal, vertical or diagonal) of at least five balls of the same colour. If you do form such lines of at least five balls of the same colour, the balls in those lines disappear, and you gain one turn, i.e. you can move another ball. If not, three new balls are added, and the game continues until the board is full.