You are Sentinel 1, the latest in highly maneuverable strike aircraft, and you have a mission - to protect the metropolis - but the aliens attack will stop at nothing to destroy your very last lines of defense. Your sense are tuned for battle and the attack begins.
Aliens will block your path, destroy your ship, deplete your fuel and sacrifice their lives to stop your mission. You must destroy the aliens with your rapid fire lasers before they home in and destroy you. There is no escape - you must destroy them all for they will stop at nothing.