^{From DVG - The Dictionary of Videogames}

Cosmic Chasm for Vectrex © 1982 GCE (General Consumer Electronics).

Can you save the galaxy by blowing up the alien-inhabited planet… and get off the planet before you explode? You must burrow deep inside, finding your way through the underground maze while battling the Planet Protectors. If you can get to the center, plant your one bomb and try to find your way out. It's only a matter of seconds before the planet goes BOOM!

• Joystick: Rotates your ship. Pulling back releases bomb in center chamber.
• Button 1: Drill.
• Button 2: Shield.
• Button 3: Thrust.
• Button 4: Fire.

Your mission is to penetrate an alien planet, travel through its underground maze and place a bomb by the planet's power structure in the center cavern. First, you will be shown a map of the planet, including its caverns and passageways. The blinking light indicates the cavern where you will enter the planet. You must determine the quickest path to the center.

Once in the first cavern, use your joystick to maneuver your ship and button 3 to thrust forward. The Planet Protectors will attempt to hit you, but you can destroy them first by firing dual lasers with button 4.

To get to the next cavern, press button 1, the drill, and inch up SLOWLY to the force field you wish to penetrate. If you thrust too quickly while drilling, you will destroy yourself.

Continue doing battle and traveling through the planet until you reach the center cavern. Once there, plant your bomb and find the quickest way out of the planet. You will then move on to the next, more difficult, mission.

Each cavern has eight Planet Protectors. They will try and destroy you by colliding with you. As you approach the center chamber, they will get faster. They will also get faster on each new mission.

The Planet Protectors are also aware of the danger you present. Therefore, they have booby-trapped the center of each cavern – it grows larger and larger in an attempt to squeeze you. Don't dawdle in any cavern, you may get crushed.

You don't have to kill all the Planet Protectors before you move to the next cavern. However, you will then have to battle them if you exit the planet through that cavern.

By pressing button 2 you can surround your ship with a protective shield. This shield will cause the Planet Protectors to bounce off and will prevent you from colliding with the wall. However, you cannot drill or fire with the shield on.

Unfortunately, too much energy is used by your ship in planting your bomb. Therefore, your shield will be ineffective from the time you plant the bomb to the beginning of your next mission.

The center chamber contains the planet's power structure, which you must attempt to destroy. When you get close enough to the power structure plant your bomb by pulling back on the joystick. You will then have 15 seconds to exit the planet safely.

To escape the planet safely, you can either travel back through the path you carved or any other you'd prefer. If you enter a new cavern, you will be faced with additional Planet Protectors. Don't forget, you must escape the planet, not just return to an outside cavern. Work quickly. You only have 15 seconds until the planet explodes.

You can abort your mission and escape the planet at any time by leaving the planet through any of the outside caverns. You will be given a new mission of the same difficulty level as the old.

[Not mentioned in manual—> Aborting a mission WILL cost you one ship. If you do this while using your last ship, the game will end.]

If a Planet Protector collides with you or you hit any wall, you will lose one ship. If you have additional ships left, you will return to the cavern where you were destroyed. The same conditions the existed when you entered the cavern will be in effect.

If you do not escape the planet within the 15 seconds allowed, you will explode along with the planet. If you have additional ships left, you will attempt another mission similar to the one you did not complete.

In each game you start with 5 ships.

Points are earned as follows: