Destroy the viles by turning 3 or more ships in a row the same color, while not letting the viles get too close. DON'T miss and DON'T match the colors of the plasma ball and ship, otherwise the plasma ball will target you! DON'T let the viles get to close or you will feel the sting of their lasers! The controls are very simple - only the mouse is used and plasma balls are fired by pointing and clicking. Clicking close enough to an invader ship will make the plasma balls auto-track the enemy.