Use the arrow keys to move. Press space to shoot the space monsters. The higher the level, the more points you need. In level 2 the monsters have two lives. In Level 3 the monsters have 3 lives. In level 4 the monsters have 3 lives and go in a zigzag and so on. You should be able to figure out the rest on your own. There are 7 levels in total. If you have 100 points and have shot 100 bullets there is a surprise.
I give omdn01 most of the credits. (I added the highscore function).
