Arrow up or space - Fire

Arrow down or M - Fire a missile

P - Pause on/off

S - Start the game

Left arrow - Move spaceship to the left

Right arrow - Move spaceship to the right

Escape - End the game currently playing

If the attacking spaceships comes all the way down to your spaceship you lose two lifes

Bonus lifes every 10000 points

When the ufo passes - try to hit it, when you do you gain 1000 points and a new missile

500 points for completing each level

The attacking spaceships may have one more bullet on the screen for each level, the game also moves faster

You may have 6 bullets on the screen at any time (and only one missile)