The PC and SNES versions of the game feature a number of minor gameplay differences. The most important difference between versions is the plot.

In the PC version the player controls a member of the "United Earth Empire" ("Empire" in short) a futuristic version of United Nations. Although it's called "Empire," the organization is not a dictatorial government. However, the adversarial Zorgeuf's force is. After conquering all space colonies, Zorgeuf sets his eyes on Earth and the player must take up arms to protect the planet.

In the SNES version the player controls a member of the "Space Colonies Allied Forces", an alliance formed by the independent space colonies. The primary mission is to take the battle to the Earth, which is currently in the grip of Zorgeuf's empire. The goal is to save the humans living on Earth who are being oppressed by Zorgeuf while securing the future of Space Colonies.

A special "Master Edition" of the game was released by Namco and Mindscape for PCs in 1995. In the Master Edition the characters were given voices, the overall look of the GUI changed, and the game featured better sound and warning effects.

Allies (United Earth Empire Forces / Space Colonies Allied Forces)

J.R. Bowman (PC version) / Ernest Bowman (SNES version): Intelligence Advisor. On every mission in the SNES version, he gives the player advice on how to go into the battle. In the PC version he looks slightly younger and has brown hair while he has white hair in SNES version. His past is unknown except the fact that he was recruited by the player's forces three years ago.

Sergeant Onaka Kraft: Sergeant Onaka Kraft was born on the post Antimatter War island of Hiroshima, Japan. She attended public schools and studied electronics in post-secondary school. She enlisted in the Army of the Empire after graduating five years ago.

Kraft received intensive communications training from the Army and soon qualified as a radio operator. She received the Meritorious Service Award for maintaining her post during the energy refinery disaster on Perth Island two years ago. She then joined the elite 43rd Communications Squadron and assisted in setting up the new worldwide ultra-short wave secure radio communications network. Kraft subsequently became the primary operator for all video/message and message only transmissions routed through Empire Headquarters.

She is on loan to us from the 43rd for these operations. She is the player's single conduit to the outside world, and her only duty is to relay messages of enemy commanders to them. All communications with the rest of the player's crew, allies, and enemies go through her.

Sergeant Harlan Sanders: First Sergeant Harlan Sanders was born on Johannesburg Island shortly after the Antimatter War. His mother and father were members of the United African Army Corps of Engineers and he showed aptitude to follow in their footsteps early. At age fourteen he submitted drawings that later became the plans to the first secure fresh water source on Delhi Island.

He enlisted in the Army of the Empire after graduating from the Dr. Stacey Santa Cruz School of Engineering. Sanders immediately distinguished himself by designing the multiple deflection system that is currently used on the armored gun pods. He was also responsible for the primary design and prototype construction of the Metal Marines. Calling Sergeant Sanders a logistics genius is an understatement. He and his crews have performed near miracles when faced with construction challenges under fire, and is a testament to the importance of these operations.

Sanders only appears in PC version when a Metal Marine unit is constructed. Why he is a mere sergeant despite the fact that he graduated from engineering school is unknown.

Adversaries (Space Colonial Forces / Zorgeuf's Empire)

Commander Bill Garland: The first character the player encounters in the game. Bill Garland was born on Earth in the old North American Protectorate. He was educated in public schools and attended the General H. Norman Schwarzkopf Academy of Military Sciences. As a junior officer he was assigned to Embassy duty at the Io Colony. It's believed that this experience is what drove him to become aligned with the Colonial Rebellion Legions and to desert the United Allied Earth Forces just before the Antimatter War. He attained the rank of Commander under Zorgeuf the Great after leading several guerrilla raids on the moons of Mars. Profile of his tactics is based largely on information gained during these raids.

Commander Garland is a bull-headed opponent, often going into battle at the first chance he gets. He has little experience leading a highly mechanized army or defending a standing base. It's rather dubious that Zorgeuf the Great has high hopes for his success. In fact, Zorgeuf the Great probably has the player facing Commander Garland and his minimum assets first in the hope that he will either accidentally defeat you or you will get discouraged and go away.

Commander Garland is not a very aggressive opponent, he tends to be somewhat defensive in his tactics, and will use his assets to build defenses. His professional military training prevents him from making mistakes when he gets upset. On the other hand, his attack strategies are poor and he does not use his reconnaissance information to his advantage.

Commander Joan Rile: One of the other opponents the player will face during the game. Joan Rile was born somewhere off planet either shortly before, or after the antimatter war. Her education and general background are unknown, but it is clear that she has had a rapidly ascending career. She is definitely a product of the new generation of warriors.

Incredibly ambitious and hot-headed, she has a tendency to make mistakes when the pressure is high. She is somewhat smarter than Commander Garland about planning her tactics and building new assets accordingly and although she has great knowledge of offensive tactics, she spends little time on defensive tactics. Like Garland, she doesn't use knowledge gained from previous attacks to her advantage.

High Commander Liften Schwaltz: Basically the right-hand man to Zorgeuf the Great, this tough German was born in Berlin shortly after World War III united Europe once again. He was a student of Obenfurur Heickel and soldiered as a mercenary for the oil producing countries. Many believe that his terrorist tactics are solely responsible for continued dependence on oil decades after cheaper energy sources became readily available. Some also blame him for starting the Antimatter War.

He may appear to be out of control during gameplay, but he actually keeps a cool head and places his defenses and offenses properly. He does not often make mistakes with his attack strategies, but his one weakness is long term planning. It is believed that he starts each battle with a specific plan in mind and then is incapable of making mid-course corrections. The player may also notice that if he discovers assets where he did not expect them, he may ignore them or forget that they were there.

Nikolai I. Zorgeuf (Zorgeuf the Great): The early life of Zorgeuf is unknown, but it has been said that Zorgeuf worked his way through the ranks of the Earth and Moon Colony Militaries. The early history of Nicolei I. Zorgeuf, Commander of the Colonial Forces, is unknown. It is rumored that he may have worked his way up the ranks of the old Romanian Army as a strategic advisor or possibly a member of the Secret Police. His first confirmed appearance was during the workers' rebellion at the ore processing plant on Galileo. Since then, he has left a bloody trail of conquest across the entire solar system.

He has managed to convert, bribe, or intimidate a huge army with vast resources. There is no doubt that his ultimate goal is complete dictatorial control of the entire human race. Eventually after the Antimatter war, he took control of the remaining governments.

When the player eventually faces Zorgeuf, he will be a tough opponent indeed. By then he will have used up his lesser commanders and taken control of his army personally. The player will see that he is an incredibly aggressive leader, with no regard for the well-being of his personnel. He will tenaciously destroy any of the player's assets that he discovers. If he is given enough time before a battle starts, he will be well dug into a defensive position, but those forces will pretty much be on their own, and will receive little or no reinforcements.

His greatest weakness is that he is easily upset by setbacks, especially setbacks in building an antimatter missile, and tends to make tactical mistakes when he is pressured. He also has an elite Metal Marine unit called "The Wolf Division" consisting of extremely talented pilots fiercely loyal to Zorgeuf and state-of-the-art metal marines.

Zorgeuf is obsessed on getting his hands on the Antimatter missiles, and the player must prevent this from happening no matter what.

Offensive Structures

Metal Marine Hangar

Large hangars that can house Metal Marines. If the player's base is attacked by enemy Metal Marines, your Metal Marines in the hangars will engage them as long as they are in range. If the Metal Marine inside the hangar is destroyed, the player can build another one using the "Build Up" icon (PC version only). It's also possible to upgrade the Metal Marines using "Build Up" icon. Their color will change to Silver from Gold.

In SNES version, you cannot rebuild destroyed Metal Marines in hangars. You must bulldoze the empty hangar and rebuild the Metal Marine.

Surface-to-Surface Missile Battery

Missile launchers designed to attack the enemy's island. They are powerful enough to destroy most structures excluding bases and Gun-Pods. However missiles are rather easy to shoot down with interceptor missile systems and missile launchers are very easy to destroy and completely defenseless. They can be upgraded to launch two missile at one time. They damage to all units in a 3x3 square radius.

ICBM Silo

An gigantic silo housing one of the doomsday weapons that turned the Earth what it is now. This building is a large structure which requires 3x3 building space. It takes a long time and enormous resources to build. Also, if even one of its parts are destroyed during the enemy attack, the player must build it again from scratch. After it's completed the player will also need a large amount of fuel to attack enemy's island.

When the player finally attacks however, this missile will destroy everything in its blast radius except bases. It's impossible to shoot it down with interceptor missiles and the player's only chance of stopping it is to destroy it before construction is finished.

Defensive Structures

Interceptor Missile Battery

Those anti-air missiles are your only chances of defending an island from enemy missile strikes and air landings. While they can destroy enemy missiles in one shot, a few shots are required to shoot down the enemy dropships. Their accuracy is determined with their range to target and how many AA Radar systems the player has. They can be upgraded to launch two missiles at one time, which increases their damage. Interceptor missiles don't need any energy to attack and they are completely defenseless except enemy missile attacks.

Gun Pod

Defense pillboxes armed with cannons and machine guns to defend the base from attacking Metal Marines. They are cheap and easy to produce. Although their firepower and range is rather weak, their defenses are good against missiles and especially enemy Metal Marines.

Interceptor Anti-Air Radar

Each of these radar installations will increase the hit rate of the player's interceptor missiles by 5%.

Mine field

Anti-Tank mines buried to the ground will damage any Metal Marine that walks on them. Although their firepower is weak, they cannot be spotted by enemy units, including missiles or dropships.

Decoy Base

A fake structure that looks like a base. It can be used to fool the enemy. Although it's not as tough as real bases and cannot stand an ICBM, it is still durable and can hold several hits, especially missile attacks. In single player games, computer uses more decoy bases as the game progresses.

Camouflage Structure

Those fake civilian structures can be built on any clear terrain, base or decoy base to hide them from the enemy. Since the enemy must first destroy it to reach the player's base, it can also be considered an additional armor for bases.

Although they can fool the enemy, a civilian structure in the middle of an enemy base will surely draw attention.

Logistics & Support Structures

Base

The command and control center. The player can place three of those to their island. If all three are destroyed, the player will fail the mission. Victory will result if the player destroys the enemy's three bases. Although they are durable and can withstand to ICBM attacks, they are defenceless. Bases do not require any money or fuel to construct. Metal Marines are especially effective against bases while missiles do moderate damage.

War Administration Headquarters

These administration buildings will give extra credits for every two seconds that they are intact. Normally the player will gain $1 for every couple of seconds regardless of the situation. Increasing those buildings will in return increase the player's fund accumulation. Unfortunately they are weak and defenceless. And it's rather hard to build this kind of structures while focusing on attack and defence. This building has only moderate protection against enemy missile attacks.

Energy Plant

These energy plants house the rocket fuel required for missile attacks and transports. Normally, just like money, the player will gain one energy point for every two seconds. Increasing the number of this structure will increase the player's fuel accumulation. Another important fact is that since these buildings hold additional fuel for missiles, increasing the number of Energy Plants will also greatly reduce the time required for missiles to reload. They have moderate protection against missile attacks.

Factory

Every thing the player constructs on their island requires a certain amount of time to be completed. Building more of these buildings will decrease the time required to construct and upgrade the player's weapons & equipment. They have moderate defence against missile attacks just like the Energy Plant and Administration Headquarters.