Move the grey ball to activate all kind of effects that enable you to open the doors and reach the end. All the items from the scene can be useful while you progress, it's a matter of trying until finding the right way to the end. With 81 levels of increasing difficulty. | Click on a colored square to enter a level; while playing, move the grey ball with the arrow keys; you have to activate effects like changing the color of the portal or opening and closing doors, and to do this all the objects in the scene can be useful. |
