Installation 03, also known as Gamma Halo to the UNSC, is one of the seven Halo Arrays built by the Forerunners. It is also the second Halo installation to be discovered by humanity. Installation 03 is located in the Khaphrae system, and was managed by its Monitor, 049 Abject Testament.  Alongside 049 Abject Testament, another Monitor, 859 Static Carillon acted as keeper of the Composer's Forge, a facility located off-world but accessible via a portal on the ring.
The purpose of Installation 03, along with its brethren, was to preclude and thwart the parasite forms known as the Flood from consuming all sentient life in the galaxy. In the event of a Flood outbreak, one of the seven installations could be triggered to annihilate all sentient life within 25,000 light years. Once one ring is set off all remaining rings would activate. All seven rings could be fired at once if need be.
Very little is known about this installation, and it has yet to be directly observed, though it appears to have a red and cracked surface, indicating vast deserts and what appears to be volcanic activity. Such volcanic activity, if present, would have to be artificially induced as the Halo rings, due to their shape, lack the tectonic movement necessary for natural volcanic activity.
Before the Halo rings were fired, the Librarian hid the Composer away from the Ur-Didact on Installation 03 to prevent him from composing the rest of the human race into ancillae for his Promethean warframes. As well, the Iso-Didact held a meeting with seven monitors and the surviving Lifeworkers to figure out who would be the caretakers of each ring. Given the Activation Index, monitor 049 Abject Testament was chosen as the caretaker of Installation 03.
In August 2552, the freighter ship, Floral Express, tried to escape the Battle of Tribute and entered slipspace to a random destination as per the Cole Protocol. On October 8, 2552, the ship exited slipspace near the installation. On October 25 of the same year, and based on information recently obtained at the Battle of Installation 04, ONI teams had started and acted out neutralisation protocols on the installation.
Put Into Standby
During the Battle of Installation 05 on November 11, 2552, a signal was sent to this Halo from Installation 05, putting it on standby mode. A readout from Installation 05's Control Room showed that Installation 03 was fully prepared to fire on demand.
A more comprehensive readout was later observed on Installation 00 during the Battle of Installation 00 by the Arbiter, John-117, and the High Prophet of Truth. John-117 deactivated the installation before it could be fired.
Shortly before March 2553, Installation 03 began to be researched and monitored by the UNSC Ivanoff Research Station. During this time Marine and Spartan-IV teams trained on the ring's surface. They also conducted sweeps and searches of the ring to find any potential sites of Flood contamination and any notable Forerunner artifacts.
That same month, Dr. Halsey was imprisoned on the station by Admiral Parangosky for lying to her about the flash clones used to replace kidnapped Spartan-II candidates. Her imprisonment on the station most likely led to her creating several different audio logs about the recovered artifacts.
The Composer was recovered from the ring by the UNSC Infinity and taken to the Ivanoff research station prior to 2557, a process which the head of the station, Dr. Sandra Tillson, claimed to have taken three months. During research, an accident involving the Composer killed the entire research team. According to Cortana, this accident is also where the UNSC Infinity found the coordinates to Requiem.
Attack on the System
- Main article: Raid on Ivanoff Research Station
On July 24, 2557, the Ur-Didact and Jul 'Mdama's Covenant attacked the station trying to recover the Composer. The Ur-Didact used the Composer to compose everyone on the station. John-117 used an F-41 Broadsword docked on the station to pursue the Didact. After this attack, it is unknown what became of the station.
During this attack, a contingent of Covenant had landed in a jungle region of the ring and secured a Forerunner artifact called the Conduit from a structure they called the Altar. A currently unknown Spartan-IV was deployed to the surface of the ring to reacquire the Conduit from the Altar.
In and around the time of the Ur-Didact's attack, Spartan-II Black Team had been assigned to the ring along with a research team. The science team created a camp on one of the installation's deserts. On July 25, the Didact had been sent through the slipspace portal aboard the Mantle's Approach to the Installation, after John-117 had defeated him at the New Phoenix Incident. The Didact and his Prometheans attacked and killed Black Team and these scientists.
The Didact's Plan
In and around the same time as all of this, the monitor of the Composer's Forge, 859 Static Carillon, attempted to contact 049 Abject Testament after a slipspace portal opened into the Forge. When he got no response from the monitor, he decided to travel through to Installation 03 to investigate. He encountered the Didact on the surface and at his request, he asked the monitor to take him to the portal that led to the Composer's Forge, in the Composer's Abyss.
On July 25, by the orders of Admiral Lord Terrence Hood, Spartan-II Blue Team was deployed to the surface of the installation to investigate the disappearance of Black Team and the science team. They had soon discovered that both teams were killed and eventually found their way to the Composer's Abyss and entered the slipspace portal to the Forge. Once the team arrived at the Forge, they encountered the Ur-Didact. The Didact, requested Carillon to move Installation 03 over the planet that housed the Composer's Forge. Blue Team followed as the Didact took one of the other Composers back to the installation. They confronted him within the Abyss and were nearly killed until Static Carillon ambushed him and teleported him to Installation 03's control room.
John-117 managed to acquire the Activation Index for Installation 03, which was dropped after Static Carillon ambushed the Didact. He and Static Carillon followed the Didact to the control room while the other Spartan's waited in the team's Longsword. John, gave the index to Static Carillon who could then gain control of the installation's systems. Static then detached the plate of the ring that housed the control center and let it free fall into the planet that housed the Composer's Forge. Meanwhile, Static was busy maintaining the rings integrity as the plate that was removed, caused massive cracks in the surface of the surrounding plates. The surrounding plates were not connected, which would have closed the loop, allowing the ring to not fall apart. John, still on the control center plate, was then teleported away by Static Carillon before he was burned up. The Didact and the Forge were burned away by the plate. Static Carillon took the ring to an unknown location to repair it and for safekeeping purposes.
- It appears to have a Venusian surface. It is likely that images of Venus' surface were transposed onto the ring's hologram for Halo 3.
- This ring is often mistaken for Installation 05 because of the order the rings appear in The Covenant. Although it is not so, because Installation 05 is the fifth ring from the platform on which Truth and the Jiralhanae reside rather than the direction in which the player enters the area, whereas the fifth ring in from the entrance has an apparently volcanic surface. In-game data files confirm this fact.
- Unlike Installations 04 and 05, which orbit large gas giants, Installation 03 orbits a rocky planet, whose face has been shattered as a result of a fairly recent impact event; the debris from the impact, still aglow as of 2557, has collected to form a dense asteroid field in orbit over the planet as well as Installation 03. However, it is possible that this is just a moon and the gas giant hasn't been seen.
- The numbering of the rings concerning the IWHBYD ring sequence is the opposite to the rings' actual installation numbers.
- Like all Halo installations, Installation 03 derives its power from the Power Rooms which are connected to other Power Rooms placed around the whole ring.
- Defender-class Spartan-IVs were originally stationed on the ring at some point before or during 2557.
- When seen from space, large circles of light are visible on the dark side of ring, indicating there are Forerunner cities or perhaps large UNSC bases on the interior surface.
- Installation 03 is the first Halo Installation seen in the series that is not attempted to be activated on-sight. It is, however, attempted to be activated from Installation 00 during the events of Halo 3.
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- Halo Waypoint - Halo 4 Essential Visual Guide Info Inside
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- Eleventh Hour Reports, #5
- Halo 2 - The Great Journey
- Halo: Glasslands page 428.
- Halo 4: The Essential Visual Guide
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