You can leave the safe zone by pressing "SPACE"
You can be killed by missiles, but only if they hit you directly.
Starting with level 2, the enemies will start following you (but only if they are faster and can catch you).
There are various bonuses and penalties apperaing randomly on the map. Bonuses are green and penalties are red
If you run out of lives, you will have to start over.
To win the game, you have to win all three levels.