Unless I skipped over something, this game has come

closer than any BASIC game before it to imitating the

likeness of Space Invaders.  To my knowledge, only

three things are different from the original besides that

the bullet's x-coordinate is equal to that of the ship:

1)  No UFO's overhead

2) No shields

3) The aliens don't shoot back

Besides these three things, this game and the original

are very much the same.

There are two ways in which it gets harder as you

progress through the levels:  The aliens speed up.  Larger

groups of aliens come, too.

When you get a good ways into the game, a weapon

upgrade makes shooting down aliens go faster.  On any

level, you lose when an alien gets to the bottom of the screen.

You start out with two lives and get one every four levels.

Also, every fourth level is a checkpoint on which it is impossible

to get a game over.

Use the arrow keys to move back and forth.  [2nd] fires.