
When you start the game, your spaceship will be in the middle of the screen with four large asteroids heading toward your ship. After all the rocks are destroyed, the next round begins. The number of initial large asteroids depends on the round number :
Round 1 : 4
Round 2 : 5
Round 3 : 6
Round 4 : 7
Round 5 : 8
Round 6 and up : 9
Your job is to blast those rocks, however, when you blast them, they break up into two medium rocks. Blasting a medium rock gives you two small rocks. Note : There is an exception to this rule. The game program only allows 24 asteroids on the screen at any one time. If the screen already contains 24 asteroids of any size, then when you shoot a large asteroid it breaks up into only one medium asteroid, and when you shoot a medium asteroid it breaks up into only one small asteroid. You can completely destroy a large asteroid with only three shots instead of seven when the screen is filled up like this.
In addition, you have to contend with large and small saucers and the 'death stars'. On the first couple of screens, you can sit in the middle and blast rocks. Be aware that a saucer will enter which will cause you to move lest you be hit by its shots. In addition :
1) You can have four shots on the screen at any one time. This is useful for when you are blasting rocks at close range. You can pretty much drill them to dust.
2) Your shots 'wrap around' the screen. This means any shot that goes past the edge of the screen will reappear on the opposite side traveling the same direction. The saucers also have 'wrap around' shots.

After 10,000 points, the small saucer becomes a permanent part of the game. You can no longer sit in one place since the small saucer is able to track your ship and take you out with the first or second shot.

Your shields have a maximum life expectancy of 17 seconds. Each collision with a rock takes away about six seconds of shield time. Once your shield runs down, it can not be recharged. In other words : use your shields as little as possible.

Although there is danger from the rocks and saucers, you can also be a danger to yourself. Use the thrust carefully or you will find yourself careening out of control on the screen. Some players get really good, however, moving around and shooting.

For those desired high scores, you can use the hunting trick. It goes something like this :
1) After 10,000 points, the small saucers appear. They are worth 1,000 points apiece. First, blast every rock until you have one small rock left.
2) Go sit in the upper left or right corner of the game screen.
3) If the small saucer appears from the side you are on, then you can blast it before it gets off a shot. If it appears on the opposite side, use the shot 'wrap around' to take care of it. Some people have done this for hours on end and racked up scores in the millions. Of course, it takes a long time at 1,000 points a pop.
4) Also keep in mind that the small saucer can wrap shots so you may have to move out of danger.
5) Unlike in "Asteroids", the small saucers fire a greater number of shots so hunting is more of a challenge.
6) After 60,000 points, the accuracy of both UFO's goes up dramatically.

The 'death stars' make their appearance in either the first or second wave :
1) It appears on the screen just lazily floating around. It can only be broken open by laser fire (yours or the saucer's).
2) Once open, the pieces pursue the player. Hitting one of the diamond-shaped pieces breaks it into two triangular pieces.
3) The best way to defeat this enemy is to accelerate forward, then turn quickly while shooting. This causes you to fly backwards while shooting at the pieces.