You are the commander of a mobile early-warning defence base - our solar system's last defence against alien invasion. You must destroy the incoming missiles before they destroy your radar stations.
Move the mouse to aim the defence missiles, click the left mouse button to fire. Press 'M' to turn the music on and off; press 'S' to turn the sound effects on and off..
Warning! You have limited resources of defence missiles - use them wisely to get the High Score! Once all your radar bases are destroyed, there is no hope for us on Earth....
Good luck, commander. You are our last hope!