Use the arrow keys to move the falling polycube around in space. Hold the Ctrl key and press the arrow keys to flip the polycube forwards, backwards and sideways. Hold the Shift key and press the left or right arrow keys to spin the falling polycube. Press the Space bar to drop the falling polycube into place for the highest bonus. After filling a layer, each remaining polycube will be shown individually to reveal any empty spaces. Press any key to cancel and resume play. Use the + and - keys to adjust the transparency of the stack.