INTRODUCTION

The Forerunner are shrouded in mystery. Although their cyclopean architecture still remains, they have long been absent from their own creations. What little we know of them is explained vicariously through their machinery and their automatons. Clearly, they were technologically superior to both Humanity and Ourselves. Their empire spanned at least this galaxy, encompassing both Normal reality and Slipspace.

At one point in the Forerunner's history, they encountered or created the Flood. For whatever reason, they felt it was necessary to contain and study the Flood, in colossal facilities capable of omitting sentient life from the entire galaxy, rather than destroy them outright. Their allowance of the Flood's perpetuation could be considered an inexcusable lack of foresight for such an advanced civilization, though without knowing their precise reasoning, the passing of judgment is problematic.

Their relics are not restricted to Halo 04. The Aztec-like stones of C'ort Azur, the arches and weathered inscriptions of Sigma Octanus IV, the intricate caverns and 3km holographic dome beneath ONI's Reach complex, and the ancient stepping-stones of the Grunt's homeworld. The Prophet's themselves claim to have evolved on an abandoned Forerunner planet, not to mention the countless installations undoubtedly pilfered to allow, us, the Covenant, to have achieved our current levels of technology, all give testament to this galaxy's permeation.

But who were these Forerunner; these Truth-givers? The Covenant, garbed in their glyphs, homage to those symbols depicted in the interiors of Halo's buildings, whereas Humankind seems all too at home, and recognized. Have they been destroyed, taken leave, or are they now "in chains"? Much remains to be answered.

THE CONTROL ROOM

The Control Room was situated atop a massive pyramid-like structure, and held the controls that controlled Halo's functions.

343 GUILTY SPARK, THE MONITOR

343 Guilty Spark is the Monitor of "Installation 04", also known as Halo. He has been on the ring for 101,217 years (local time), serving and maintaining the installation. Little else is known about him other than that he is a type of Forerunner AI, but encased in a metal orb-like body, and is capable of motion. He possesses much knowledge on the Flood and the Forerunners, though he has not been forced, coerced, or persuaded into releasing any of it.

He is made of a near indescribable, unknown metal. He seems to be effected by energy surges but can recover remarkably quick. He can access almost all Halo's controls from anywhere within the installation without tapping into anything. He uses his Sentinels for self defense and seems awfully chirpy and full of himself commenting on how he is a genius and often humming to himself.

Due to his long time on the artifact without any kind of companionship it is quite possible that he is totally insane, though how an AI could become insane is unknown.

HALO INSTILLATION 04

The name "Halo" is derived from Covenant battle transmissions, translated by Cortana. A more literal translations would be "Ring of Heaven", or "Ring of the Gods". Halo orbits a large gas giant (Earth Survey Catalogue Number B1008-AG, nick-named "Threshold"), suspended at the Lagrange point between the planet and it's largest moon, Basis. The ring has a 24-degree axial tilt from the gas giant's orbital plain, which means that any point on the surface receives sunlight for half of the time it is on the sunny side of Threshold, and for none of the time it is on the dark side. This gives the ring a somewhat unusual day-night cycle in which it is dark three-fourths of the time. There is of course, no sunrise or sunset in the traditional sense.

Halo was built to study and contain the Flood organism, and to stop it's spread. It is also a massive weapon--it can destroy all life within a 25,000 light year radius. It is unknown how this weapon functions, and if it is even possible to survive within the blast radius. Halo is honeycombed with tunnels, caverns, rooms, facilities, canyons, ravines, and mountains. It was created with natural ecosystems, including small organisms, such as insects, and even small bird-like animals.

Halo is home to 343 Guilty Spark, an AI, and Monitor for Installation 04. He was somewhat misleading when he lead the Master Chief to activate Halo's "defenses" against the Flood and Covenant. If not for Cortana's intervention, the Chief would have inadvertently triggered Halo's weapon. Halo was destroyed after the Pillar of Autumn's fusion core exploded. The pieces of the ring now drift in space, hurtling toward Basis and Threshold, being caught in their gravity wells.

Halo holds great religious significance for the Covenant. Soon after Halo's destruction, a Covenant flagship, with it's armada, exited Slipspace in the system. The UNSC AI Cortana deciphered from their transmissions, and from their data core that the "Guardian of the Luminous Key" was due to arrive there for some sort of ceremony. The Covenant truly have a high regard for HALO.

THE LIBRARY

The Library was a huge labyrinth maze of corridors that spanned a large portion of ground underneath of Halo's surface. It housed massive caches of information in it's walls, and the Index was housed within as well.

LIGHT BRIDGE

The Forerunners built Halo with many interesting and unknown technologies, one of which is the energy bridge. It is a bridge comprised of "solid" energy, which can support an enormous amount of weight. It is unknown how the energy solidifies enough to support so much weight, though it is possible that the energy particles are simply so dense that objects cannot pass through it.

PHASE PULSE GENERATORS

Halo's main weapon is powered by three phase pulse generators. These generators create the power used for Halo's weapon in an unknown fashion. They are susceptible to close range EMP discharges, and destabilize if they come in contact with an EMP pulse.

THE SENTINELS 

The Forerunner had abandoned the Halo, Installation 04, some time ago, leaving their robotic compatriots behind to defend and monitor the installation. Seeing the Master Chief and Cortana breach protocol and refuse to activate Halo upon the Flood's release, 343 Guilty Spark turns Halo's only known internal defensive system on them: the Sentinels. 

Controlled by the Monitor of the Halo installation, the Sentinels are the guardians of Halo, and enemies to all. They appear to be hovering drones that are armed with some sort of controlled stream of energy, strong lasers that can cut through their designated targets. Deadly and precise, these lasers are used to control the Flood, though they can only manage them for short periods. When not engaged in combat, they contract into smaller forms, concealing their weaponry. Sentinels seem to be very weak to all Covenant weapons. Black Sentinels are equipped with what is presumably Forerunner shield technology. Energy shields, unlike the weaker Silver variants.

THE SILENT CARTOGRAPHER

The "Silent Cartographer", as referred to be the Covenant, is Halo's map room. It can pinpoint and access every room or location on or beneath Halo's surface. Little else is known about this map technology.

The Silent Cartographer is protected by an elaborate security system. This system can only be activated and deactivated by manual physical contact. In order to access the Silent Cartographer one must enter a first building to disable the security system, and then enter a separate structure which contains the map room. This gives the map room double protection making access difficult and defense much easier.

TELEPORTATION GRID

Halo was built with an extensive teleportation grid that covers the entire ring. It is unknown exactly how the grid digitalizes matter and transports it, but it is theorized that it may be simply a miniature, and more precise version of slip space technology, in that it transports matter in the same way UNSC and Covenant spacecraft travel through the galaxy.

The Monitors of HALO can easily tap into the Teleportation Grid for incredibly fast movement throughout the structure.