Move your player on the centered grid and prevent pills from reaching you as long as possible !! If you face a pill of the same color then 'space' will delete it from the board. Otherwise you can swap this color and use it to delete another pill of the right color. A counter is displayed on the upper left part of the screen and shows how many pills need be deleted before you reach another level (as indicated on the upper right part). As you reach the quota, the game speeds up hence adding a challenging difficulty. That's when we'll see how good you are :)