Survive the alien invasion as long as you can. The more ships and asteroids you destroy in the process the better your score.
Escape or P: Pause / Settings.
W or Up Arrow Key: Accelerate forward.
S or Down Arrow Key: Accelerate backwards.
A or Left Arrow Key: Rotate to the Left
D or Right Arrow Key: Rotate to the Right
Shift or LMB: Shoot machine gun.
Space or RMB: Shoot rockets.