///INTEL: THE FLOOD - A BRIEF HISTORY///
The extra-galactic parasite known as The Flood, played a brief but all important role during the closing years of the Human-Covenant War. While little is definitely known by both the UNSC and the Covenant, the parasitic species colloquially called the Flood; is in truth a both a form of punishment and a test for the denizens of the Milky Way. The true origins of the Flood are a mystery but it is known that the Forerunners, much like humanity later; rose up against the Precursors and nearly wiped out the species. In retaliation, the last surviving members of the Precursor race, brought the Flood from another galaxy to prove that the Forerunners were unworthy of what they called “The Mantle”.
For three hundred years, the Flood battled the Forerunners. The Forerunners, in desperation built and ultimately activated the Halo Array; a series of planet sized rings with enough firepower to eliminate all life in the galaxy capable of sustaining the Flood. The Forerunner took precautions against the annihilation of entire species by taking them to the Ark, the installation outside of the kill distance of the Halo Array. The Ark preserved and protected these species after the Forerunners fired the super weapon, and automatically returned each species to its planet of origin after the majority of Flood had essentially starved to death. Those that did not entered a state of hibernation and bided their time.
Thousands of years later the Flood were unleashed yet again during the Covenant War in 2552 on Installation 04. In order to prevent the Flood from fleeing Halo, Spartan-117 known better by his rank of Master Chief detonated the UNSC Pillar Of Autumn’s fusion reactors and destroyed the ring. The UNSC came into contact with the Flood again on Installation 05 also known as Delta Halo. Here, the controlling Flood intelligence known as the Gravemind, made its presence known. Not wishing to be deprived of sustenance again, it aided the Master Chief and the disgraced Elite commander now known as the Arbiter in halting the activation of Delta Halo.
While the UNSC focused on defending Earth from the Covenant invasion, the Elites’ split from the alien alliance and focused on keeping the Flood contained on the infested Covenant capital, High Charity. One ship would break through the Sangheili blockade just as the Covenant leader, the Prophet of Truth activated the portal that led to the Ark where he planned to activate the six remaining Halo rings. Pursuing the Flood ship to Earth, the Sangheli ship Shadow of Intent aided the UNSC in sterilizing the Flood presence on Earth. The Shadow of Intent along with the crew of the UNSC Forward Unto Dawn, followed Truth and the bulk of his forces through the portal.
After ascertaining the Prophet’s location, the Gravemind once again in the act of self preservation, allied itself with the Master Chief and the Arbiter. The numerous Flood troops at its disposal eliminated Truth’s remaining guard, clearing the way for the Master Chief to stop the Ark from activating the Halo Array, and for the Arbiter to assassinate the Prophet for his deceit. With the immediate threat neutralized, the Gravemind laughed manically, as its forces surrounded the duo with the Arbiter remarking, “We trade one villain for another”.
The pair escaped to discover that the Ark had built a replacement Halo for the one the Master Chief had destroyed months earlier. Formulating a plan to activate the unfinished ring and destroy both the Ark and the Gravemind, the Master Chief made his way into the Gravemind’s stronghold on High Charity to rescue the AI that had helped him destroy the first Halo. After suffering months of torture at the clutches of the Gravemind, the AI Cortana was in a fragile state. Upon seeing that the Master Chief had fought through hell to save her, she regained her composure and showed him that she still posed the activation index that would allow her to destroy the new Halo.
Along with the Arbiter and Sergeant AJ Johnson, who had survived and escaped the first Halo, the two fought through the Flood that were defending Halo’s control room. Upon discovering that they planned to destroy it, the ring’s caretaker, 343 Guilty Spark mortally wounded Johnson and attempted to kill the Master Chief. With a dying Johnson’s aid, the Chief defeated the rampant Forerunner AI and began Halo’s selfdestruct sequence. The Spartan, Cortana, and, the Arbiter all made it aboard the Forward Unto Dawn just as the unfinished and unstable Halo shook itself to pieces trying to fire, and managed to destroy a significant amount of the Ark in the process.
Unfortunately, the Ark was too damaged to sustain the portal back to Earth and collapsed, severing the Dawn in half. The half carrying the Arbiter made it successfully back to Earth. The half carrying the Master Chief and Cortana did not and drifted in space for four years until crashing onto Requiem.
As there are still six Halo rings remaining, the UNSC continues to develop counters to a potential Flood resurgence and the UNSC Infinity trains Spartans to effectively combat the parasite via war game simulations.