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"Today I wish to speak to you humans out there who are choosing to fight. I know that you believe you are doing the right thing, but let me tell you the truth: there is nothing worth fighting for."
Lord Achriman[src]

The Mental War is an unofficial name for the major nine-year long conflict involving humanity and several allied species against Mental's armies, which ultimately resulted in the extinction of humanity and eventually, the destruction of Earth.


Long before the start of the war, humans had slowly begun uncovering artifacts and ruins left behind in ancient times by the Sirians, the famous and long-thought extinct race from the planet Sirius. With the understanding of this new technology, humanity had become advanced enough to stretch far across the universe.

One day, an exploratory team lead by Captain Sam Stone of the spaceship Surveyor was sent to chart out the remains of Sirius for a corporation. However, there was something unusual; the planet was surrounded by an asteroid bubble not mentioned in the records. Sam, pressured by the corporations, examined one of the asteroids, revealing hidden alien machinery and thus triggering the alarm system, bringing Mental back one hundred years earlier than usual. As humans were an advanced race, Mental saw them as a threat, and planned to eliminate mankind as part of his scheme to wipe out intelligent life from the universe. Mental also began invading planets with intelligent life on them who were allied with the humans.

The first phase (2104 -2110)[]

As he had done so with countless species before, Mental sent wave after wave of his alien hordes to attack humanity. Humanity fought against the invaders from Alpha Centauri all the way back to Earth. During one of these battles, the Battle of Alpha Centauri, Mental sent in one of his generals, Ugh-Zan IV, to lead his forces against mankind. The humans managed to wound him in battle and ended up destroying his legs. However, despite this accomplishment, Mental replaced Ugh-Zan IV's legs with cybernetic ones attached to a bio-mechanical base to make him operational once again.

Sam Stone, wracked by guilt over his involvement with reawakening Mental, joined the Earth Defense Force to atone for what he had done. He took on missions each more dangerous than the last, but somehow survived them all. Soon, he was promoted to be the captain of the Battlecruiser Saratoga, and took part in several missions across multiple planets to aid the local alien resistance in their fight against Mental.

Despite numerous EDF victories in the space campaign, Mental's armies proved to be overwhelming. Earth's colonies fell into Mental's clutches and eventually humanity had to retreat to Earth. Mental, now moving in to claim Earth as he did Sirius, began filling up the skies with Octanian Harvester Leviathans and squadrons of Octanian Raiders to ensure aerial superiority in Earth's airspace and to forcibly convert Earth's population into fodder for his forces. Having lost their spaceships, humanity has effectively become stranded on Earth.

Second phase (2110-2113)[]

A propaganda drone, used to taunt and manipulate the populace into joining Mental's armies.

When Mental's forces invaded Earth, he had several of his servants take control of his forces and had them in charge of certain tasks. One of them, Lord Achriman, took command of Mental's forces across Europe, invading countries several countries like Italy and France. Mental also had him use whatever tools of propaganda there was to ensure that humanity complied. One such method was deploying Propaganda Drones into the streets. The drones would tempt anyone in the city to join them so they could be processed, taunting them and assuring the humans there was a better way to live than their current way of life. People who were still alive in any cities were quickly captured by Harvester Drones; the drones took the captured humans into the Harvester motherships, where they would be processed into alien fighting machines for Lord Achriman.

Final phase[]

With the destruction of the Tunguska portal and defeat of the remaining Octanian forces during the Tunguska Offensive in 2112, Mental decided to stop processing the Earth's population and instead finish humanity off with massive fleets of Alcor Class Warships. This eventually lead to the battle for Earth's survival, with both sides taking massive casualties and weakening their military power. Earth lost most of its population and technology while Mental's Horde had some of its member species wiped out and had to resort to younger specimens of various species to meet demand.

As a result of Mental's invasions across the world, many cities, towns and other settlements became abandoned or took major infrastructural damage. Cairo and Rome were one of the many cities that took quite a beating; Cairo was in utter ruins and Rome was infested with polyps. By 2113, Cairo appears to have been completely deserted with no human survivors in sight.

The Egyptian Museum in an abandoned state.

The Battle for the Time-Lock[]

Main article: Battle for the Time-Lock

During the last days of the war, Mental staged a sneak attack on the Earth Defense Force's headquarters to finish them off once and for all. His forces were successful in taking them out, leaving Sam the last human left on Earth. Upon being taunted by a Gnaar over Hellfire's communicator, Sam vowed to avenge mankind by getting into the Time-Lock to kill Mental for good.

On his way to the Time-Lock, Sam was met with even heavier resistance than usual, in Mental's desperate attempt to stop him. However, Sam was able to kill every single one of them. When he finally got to the location of the Time-Lock, he is confronted by Ugh-Zan IV, Mental's last line of defense. In the end, Sam emerged victorious and heads for the Time-Lock, but before he can, Mental sends the Moon hurdling towards the Earth just as soon as Sam makes it into the Time-Lock, destroying the planet and ending the war on Earth once and for all. Though the war was over, it didn't merely end, but rather it outright stopped with an explosion.


  • It is not completely known how many casualties either side took during the war. It is known the humans took out many of Mental's generals, such as Lord Achriman, Ugh-Zan IV, Ugh-Zan V (In Oslo), and Ugh-Zan VI. It is known that the humans took far more casualties than Mental's forces did, and that mankind's valiant efforts ultimately did nothing against Mental's horde. All of the very few victories Mankind won were almost solely won by Sam.
  • It is known that Mental did replenish its forces with humans mutated to its twisted desires.