But to Paint a Universe

An evil creature has stolen the colors of the world, and it is a little girl's job to restore it. In order to help her, the player must solve a series of puzzles. Each puzzle has a number of colored orbs in a small board (about 5x7), where some squares are specially marked; click on an orb and it vanishes, together with its adjacent colored neighbors in a straight line (and new orbs fall into the board). Get all marked squares to contain orbs of the same color to move towards the end of the level. Fail to do so in a maximum number of moves and you fail.

That said, each level has a slight variation on these rules -- gravity in different directions, walls which "block" chaining effects, special orbs which push other orbs to the side, and so on. All in all, there are about 20 levels in "Adventure Mode", each one with its own rules. Play the levels on "Adventure Mode" and you unlock their versions in "Timed Mode". All levels have online leaderboards, so you can compare your scores with the rest of the worlds'.