Installation 05 (EternalSonic1997)

Installation 05, also known as Delta Halo is one of seven (twelve), massive Halo fortress worlds constructed by the Forerunners during the Forerunner-Flood war. It was the fifth Halo installation constructed, and the second to be discovered by Humanity. It orbits the massive Gas Giant named Substance and is monitored by 2401 Penitent Tangent.The purpose of Installation 05, along with its brethren, was to preclude and thwart the parasite forms known as the Flood from consuming all sentient life in the galaxy.

Activation
It is assumed that Delta Halo was built around the same time as Installation 04, circa 100,000 years before the events of 2552. It was activated shortly thereafter by the Forerunners, eradicating all sentient life in the galaxy and, presumably, destroying the Flood as well, with the exception of those specimens kept within the Halo for research. As of 2552, it had a record of 1.2 trillion simulated firings and one actual activation.

Flood Break-out
About 2 centuries prior to 2552, the Flood on Delta Halo broke free of containment and evaded re-containment due to negligence on the part of the installation's Monitor, Penitent Tangent. The Flood quickly became unable to control around the area of the Installation's Library. The Flood were kept contained by a Sentinel Wall built around the Library, but 2401 Penitent Tangent was captured. Without it, the Sentinels of the Halo lacked a controlling intelligence and so many of the structures around Installation 05 fell into horrible conditions, and most of the Installation came to look like a jungle strewn with ruins.

Even with the addition of Forerunner Sentinel Majors and Enforcers, the Flood were able to remain loose, albeit contained within the Quarantine Zone by the Sentinel Wall. The Gravemind, with Tangent in hand, resided in a chamber directly below the Index chamber within the Library, which is where it would reside until the events of the Battles of High Charity, Installation 00, Second Battle of High Charity and Installation 04B.

Battle of Installation 05
In 2552, the High Prophet of Regret discovered the location of Installation 05 during the Battle of Earth. He made a slipspace jump from Earth to the Installation, but was followed closely by Commander Miranda Keyes' Frigate ship UNSC In Amber Clad. This lead to the Battle of Installation 05 along with the Death of Regret at the hands of John-117.

Once High Charity and it's massive Covenant forces arrived, the Arbiter was told by the Prophet of Truth to go onto the Installation and Retrieve the activation Index (sacred icon). The Arbiter eventually shut down the Senitel Wall from being tasked by Brute Chieftan Tartarus, which allowed Covenant troops and forces to be deployed further onto the Ring. Eventually, the Arbiter was betrayed by Brute Chieftan Tartarus on order of the Prophet of Truth himself. It was after this that the Great Schism began.

Following was a meeting between John-177, the Arbiter, The Gravemind, the infected Prophet of Regret, and Tangent. The Gravemind sent John to the Covenant Capital High Charity and the Arbiter back to the surface of Installation 05. As the battle of High Charity raged on above, the Arbiter gained support from Sangheli, Unggoy, and Hunters to combat the forces of those still loyal to the Prophet of Truth. Eventually, the Arbiter, assisted by Rtas 'Vadum, rallied more Sangheili and Unggoy to support their operation to take over and commandeer a Scarab. The Arbiter then 'rescued' sergeant major Avery Johnson from his loyalist captors and agreed to escort him in a Banshee to the Control Center. Johnson, piloting the Scarab, destroyed the entrance of the Control Center, allowing the Arbiter to enter the structure, which was followed by a confrontation with Tartarus of which the Arbiter was victorious in thanks to help of Johnson which lead to misfire of the ring, and to the discovery of the Existence of Installation 00.

Since the Ring was heavily Flood Infested, any ship attempting to escape the ring were destroyed by the Covenant Separtists. Of course, there was one ship that escaped and managed to reach the Planet of Earth.

Quarantine & Flood Cleansing
Following the Battle of Installation 00 and the end of the Human-Covenant war, the decision was made to return to Installation 05. The Covenant Separtists' plan was to eliminate the Flood presence from the ring to prevent another incident with the Flood. Numerous Special Operations teams and High-Ranking officials were sent to kill any living flood forms along with cleansing beams being used for the infiltration.

Over 50 operations in total were made in this effort. All of them were done completely by the Covenant Separtists, and were headed by Rtas 'Vadum and eventually by Thel 'Vadamm as well. In these efforts, the chamber that held the Gravemind was completely destroyed by Covenant bobms, with Penitent Tangent being rescued prior to the desctruction which offered the sentinels' help in eradicating the Flood's presence. Some sections of the Installation were glassed,

It took from early 2553 to mid-2554 for these Operations to be complete, which gave way for another decision handled by Tangent, the Separtists, and the UNSC each.

Colonization
With the Flood finally removed from the ring, the decision was made to turn the ring into a place of living for both sides. Penitent Tangent reluctantly agreed to this, as presence of Human and Separtist forces could mean a bigger defense from the flood and the possibility of a second Covenant. This lead to several UNSC Colony ships being deployed to establish three cities on the ring, while the Covenant Separtists began establishing minor bases, along with several Sangheli clans. With effort, three cities were established alongside Covenant Separtist bases surrounding the major structures (The Control Room, the Library, etc.). The cities are often populated by both Humans and species of the Covenant Separtists.

Established Cities

 * Sagawitchewan - captial of Installation 05
 * Tài Sum
 * Scotsguard

Controversy
Following the Colonization, a great amount of Controversy started from the very start of the colonization. Many people believed it would be better to merely have Militart presence on the ring rather turn it into a Colony, though there were many people who agreed with the idea of civilians living on the ring.

Most of the Controversy came from the peole who knew Halo would be a target for many enemy strikes, and as such that was the primary argument against the colonization. However, arguments for the colonization were that by having the cities and protection there, there can be bigger chances against the flood.

Despite the massive Controversy, the colonization still occurred.

Battle of Tài Sum
Soon enough, the Battle of Tài Sum occurred in the 2560's. Though only involving the forces of Brutes and not connected to the New Covenant Empire (Sovereign Covenant Empire), this was still a major battle of Installation 05. Thanks to the orbital defense, not much of the Brute forces got down to the ring. However, some of the bigger ships and Scarabs did. Due to that, the city of Tài Sum was devastated by many enemy forces, causing the deaths of many before victory was made by the Separtist and the UNSC once more working together against an enemy. This lead to the Relaunch of the Spartan-III project, with many volunteers, one of them being Delta Halo native Brandon-G229.

Battle of Sagawitchewan
Delta Halo became the starting location of the second Human-Covenant war in 2573. Forces of the Sovereign Covenant Empire forces lead by Brute Chieftan Shipmasster Zharakus managed to engage the Orbital forces above the Ring with many of them overpowering the UNSC and Separtist guards and invading the capital of the ring. The city was soon filled with war, with many civilian and soldier losses. This battle soon became the first deployment for many of the new Spartan-IIIs. This was also the first unveiling of the Type-97 Superior Assault Platform, along with the other new vehicles (Type-19 Stealth Transport and Type-21 Heavy Assault Vehicle). Many of these vehicles, especially the mantis, were the primary source of Spartan-III deaths that occurred in the battle. However, when a Covenant Separtist Special Operations unit headed by Voru' Tuyok discovered the weakness of the Mantis and destroyed it, finally the battle became a victory. Soon enough, Zharakus was killed by a boarding operation of his ship and said ship was destroyed, it's remains falling into the waters of the ring.

Trivia

 * This is the first expansion of a canon element done by EternalSonic1997.
 * It is the first (and only) Halo installation colonized (in this fanon).