- "When we were still flesh, and our home still whole, your kind betrayed us. We, who made you. We, who gave you life!"
- ―Minerva, 1499.[src]
The Human-Isu War was a catastrophic conflict that occurred between the Isu and their human creations, with the latter being aided by those who had developed an immunity to the controlling effects of the Pieces of Eden. Little is known about the details of the war, however it served as a distraction preventing both parties from observing the impending danger from the cosmos; by the time they did, it was too late.
As a result, the war ended abruptly and with far greater casualties on both sides than either had expected. Working together, both parties recovered from the devastation wrought in the final days of the war, and began preparations to prevent such a catastrophe from happening again.
The Seeds of War
The Isu, small in number but advanced technologically, found themselves in need of a docile workforce so as to support their world. They rapidly advanced the genetic evolution of an already existing species, and humanity was born. Initially, each and every human was born with a chemical neuro-transmitter deep inside their brain, which made them susceptible to the illusions and mind controlling powers of the Pieces of Eden. However, over time, interbreeding between humanity and their "gods" caused some individuals to be born without the neuro-transmitter active, or indeed present at all.
The War and Catastrophe
Though technologically superior to their creations, the Isu beings were heavily outnumbered by humans, as they had produced many to work for them.
The human contingent was led by those who had been born immune to the hypnotic effects of the Isu's Piece of Eden technologies, as they were the children of both humans and the Isu, hybrids in effect.
Using their immunity to get close to Isu beings and kill them - seen by the Isu as betrayal of their "parents", in Minerva's words - they were dubbed "Assassins". As the Isu had slow rates of reproduction, it meant that any loss of life on their part was a heavy blow, and the skill to execute single assassinations was a perfect tactic.
The war was an even battlefield, with the Pieces of Eden and additional sense of knowledge the Isu wielded being balanced out by the massive number of humans and their comparatively quick reproduction. The humans also counted the Assassins amongst their ranks, who had the ability to resist the Pieces of Eden and possessed a diluted version of the sixth sense held by the Isu.
Eventually, however, disaster struck. War on Earth had prevented the Isu from observing the impending dangers from "the heavens", which eventually led to an abrupt, bloody end to the conflict. Both sides suffered heavy losses due to the disaster, and much of the planet was burnt to a cinder.
Meanwhile, a number of the Isu beings saw the futility of war and their impending extinction as a reason to make peace, turning their attention to creating measures (six in total) to avoid a future catastrophe from occurring.
Following this attempt, the hybrid humans led some of their species to make peace with the Isu, forgiving their "parents" for their trespasses. Together, they created the Temples, similar to time capsules, in order to warn the future. The war ended with humans claiming victory over the Isu, and the peaceful Isu members left their messages for the future, seeing their time come to an end.
After this, the leaders of the humans had in their possession multiple Pieces of Eden, and an idea of how best to lead humanity into the future. They were heavily scarred by the knowledge that their former slavers had interfered with their evolutionary destiny, and sought to bring about humanity's "rightful" path by any means necessary. Justified with this belief, they utilized the Pieces of Eden as tools, but were distrustful of any who had made peace with the Isu.
Those who represented the Assassins had always wanted to free humanity and envisioned a world where all beings could live according to their own will. As such, the Creed "Nothing is true, everything is permitted" became their philosophy, exemplifying the belief that all were free to determine their own existence. They also believed that the misuse of the Pieces of Eden to control others was against all they had worked and suffered for, as it would enslave humanity once more.
Aftermath and legacy
- "We built you in our own image, we built you to survive."
Realizing the disaster that had struck the Earth was due to strike again, the Isu constructed a number of temples, which would help to prevent the event from reoccurring. Alongside these temples, the Isu also built the Central Vault, which would serve as the meeting point of all of the information stored at the temples.
Very little evidence of the war or the Isu survived into recorded history. By the late 12th century, all knowledge of the Isu had been forgotten; however, their Pieces of Eden continued to affect the world in a myriad of ways, being seen as religious artifacts, or as a means for a number of miracles.
By the early 21st century, a number of Isu technologies had been re-discovered and reverse-engineered by the Templars to provide the Earth with a number of technological advancements, including television and the internet. The foremost amongst them was the Animus, a machine which allowed a person to relive the genetic memories of their ancestors in a virtual environment.