Communist Mutants from Space is a typical 80s-era Space Invaders-inspired space shoot-em-up. The player starts off with three reserve cannons. The object is to destroy the mutant aliens and, most importantly, the Mother Creature. The mutants hatch from moving eggs at the top of the screen. Because the Mother Creature replenishes eggs when they hatch or are destroyed, it must be defeated before the player can advance to the next wave. If a mutant or a bomb thrown by a mutant comes into contact with the cannon, the cannon will be destroyed and a reserve must be called up. A new cannon is awarded on every other wave.
An options menu allows a variety of gameplay changes; for example, the player may toggle the shield option on or off. If activated, "shield" mode allowed a player to press down on the joystick to become invincible for a short period (only one shield was allotted per level). Another feature was the "time warp," which allowed the player to press up on the joystick to temporarily slow down the passage of time for the aliens (i.e., they would move slower than usual). Additionally, the type of shot fired could be changed by activating the "penetrating fire" option (which enhanced the beam fired so that it could withstand hitting two mutants rather than a single one) and/or the "guided fire" option (which caused the beam to be moved with the joystick rather than firing in a straight line). The menu also allowed you to select the number of players.
Source: Wikipedia, "Communist Mutants from Space", available under the CC-BY-SA License.
Game Manual
Your mission: Vaporize the mutant warriors before they overrun your home planet.
About the enemy: The evil ruler of the planet Rooskee has launched a diabolical attack. A cunning Mother Creature, filled with irradiated vodka, transforms helpless slaves captured on peaceful planets into bloodthirsty COMMUNIST
MUTANTS.
The Commie Mutants attack like crazy! Wipe out wave after wave of them, and they keep on coming. And the more you vaporize, the nastier they get.
You've got trouble.
The Mutant Attack
As soon as play begins, you'll be under attack. The Mother Creature will constantly try to create more COMMUNIST MUTANT attackers. The attackers start as mutant eggs and soon hatch into nasty creatures.
Some of the mutant eggs appear not to hatch. Don't be fooled. They are actually shield-penetrating bombs in disguise.
You begin with a small reserve of anti-mutant cannons. Each time the mutants destroy one of your cannons, a reserve is called up. When the last cannon is destroyed, the game is over. You can, however, earn bonus cannons after every other wave of mutant attacks.
You'll never run out of ammunition, so keep shooting. Your cannons destroy Communist Mutants, Mutant Bombs, and the Mother Creature itself.