Forerunner

"After exhausting every other strategic option, my creators activated the rings. They, and all additional sentient life within three radii of the galactic center, died, as planned."

- 343 Guilty Spark explaining the fate of the Forerunners.

Forerunner is the translated name for an ancient race of beings that were the builders of the Halos, The Ark and the Shield World, Onyx, as well as the artifacts that were found on Reach, Earth and Sigma Octanus IV. All that we know about the Forerunners has been gleaned from these various artifacts. The predecessors of the Forerunners are thought to be another alien race known as the Precursors. The former alien faction known as "The Covenant" worshiped the Forerunners as so called gods, deriving much of their technology from Forerunner artifacts found throughout the galaxy.

Known History
Master Chief Petty Officer John-117 did this          that the Forerunner empire covered most, if not all, of the galaxy. It has also been hinted at in the Terminals that the Forerunners received their "Mantle" from the coinciding Precursors.

Later in their history, a Forerunner survey team came into contact with an extra-galactic parasite known as the Flood on the planet G 617 g. After this first contact, the Forerunner realized the great danger that the Flood posed to the entire galaxy and attempted to contain them.

The Forerunners were unable to contain the Flood outbreak, and war between the two broke loose. During the 300 years of conflict, the Forerunner studied the Flood in labs such as the one located on Threshold, looking for some sort of weakness. Eventually they created the Halo Array, a weapon of last resort designed to starve the Flood to death by killing all sentient life with enough biomass to sustain them.

At first, the Forerunners were reluctant to use the Array. The Gravemind managed to convince a Contender-class AI, Mendicant Bias, to join the Flood. Mendicant Bias soon led his massive fleet in an attack on the "Maginot Line". The Forerunner were given no choice but to activate the Halos, killing all life of sufficient biomass and cognitive ability in the Milky Way with the exception of those species safely placed on the Ark and on Earth.

Note in the last mission on Halo 3 (Halo) in the cut scene before fighting the Monitor, 343 Guilty Spark says to the Master Chief "You are the child of my makers. Inheritor of all they left behind. You are Forerunner." This may suggest that the Forerunners were succeeded by humanity. It has also helped spark rumors that the planet seen in the Legendary ending of Halo 3 is a Forerunner planet.

Forerunner Technology
Forerunner technology was highly cultivated and progressive. They managed to create solidified surfaces out of meticulous energy, construct a Halo-wide teleportation grid, as well as create and utilize a plethora of other advanced gadgets. The Halo Rings themselves, the Micro-Dyson Mark II sphere, which is connected through a portal to the shield world Onyx, and the Ark (Installation 00) are, above all others, the most significant pieces of Forerunner technology. The planet Onyx in particular demonstrates both their ability for engineering on a grand scale, and their near transcendent grasp of Slipspace technology. It is unknown how much of their technology is based on the technology of the Precursors.

Weaponry
Forerunner constructs and sentries use a broad variety of weapons, typically high-energy powered beams. These weapons proved to be very effective when battling the Flood, burning them to the point that they cannot be revived by even their compatriots. The Forerunners installed and constructed these intricate beam weapons inside their paradigm Arrays, allowing them to build an army of machines to battle the Flood without sending any Forerunner into real battle. Other Forerunner weaponry was possibly lost to the ravages of time.

The Sentinels wield orange-colored directed energy beams, used primarily for fighting the Flood. Sentinel Majors however, have a more powerful and accurate version of the beam, which sports superior energy output at the cost of overheating issues. All varieties of these Sentinel Beams can be wielded by certain Covenant and Human infantry.

Meanwhile, Enforcers are equipped with multiple packs of small rocket-like explosives launched over the top of their shield as well as weapons similar to the Needler or Brute Spiker, which fire clusters of smaller red projectiles or bolts of energy at an extremely fast rate, used mainly against infantry at close range. These mammoth constructs also seem to be able to lift vehicles using some sort of magnetic or anti-gravity grapple, before crushing even tank-sized objects between their massive 'arms'. The Constructors' repair beam can also be considered a weapon, but with minimal damage output.

The Sentinels of Onyx had significantly more powerful weaponry. They were described to be a sphere surrounded by three floating "booms", or small pieces of armor that had powerful energy shields that would suddenly "pop" into place in order to deflect fast-moving fire. Their shields can be tricked by slow-moving objects, such as rocks, which Team Saber used to destroy one of the Sentinels. Their energy weapons, described as a single golden beam that, although charged slowly, could melt straight through the armor of the Spartan-IIIs. The Onyx Sentinels also have the ability to combine energies, for different purposes, such as stronger combat abilities, or excavation purposes. Their powers are exponentially increased by this combination, and enough of them were able to combine to easily destroy two Covenant destroyers. However, the second Covenant Destroyer was caught off guard after a slipstream space jump, and the first one had its energy shields down.

In Halo 3, it seemed that even the Monitors had the ability to defend themselves against the Flood using focused beam similar to the Sentinel's beam but much more powerful. 343 Guilty Spark showed this ability in Halo. It is also quite odd and puzzling as to why 2401 Penitent Tangent didn't use this ability against Gravemind in Halo 2. It is assumed that Gravemind is likely to have damaged 2401 Penitent Tangent when he captured the Monitor, disabling its beam weaponry. It could simply be that it was not equipped with one, or that the Monitor was corrupted by the Gravemind.

Art and Architecture


Forerunner architecture is noted mainly for being large-scale and geometric in style. The Forerunners had a habit of creating natural habitats, such as those of the Halo rings, which tend to be very elaborate, with numerous extrapolations of the basic design of a construct appearing to be purely decorative. All Forerunner architecture is constructed with a special type of metal that resists deterioration, bullets, plasma bolts and fire, as evidenced by Forerunner structures standing in pristine condition 100,000-150,500 years after they were built. However, their resistance to plasma fire is limited; in Halo: Ghosts of Onyx the Elites blasted a hole in a Forerunner wall with plasma weapons. These structures employ complex geometric shapes that appear to operate in dimensions higher than basic human understanding can comprehend. The Forerunners also decorated the interiors of their structures with a complex web of engraved straight lines and applied decorative touches and designs to nearly everything that they build, from structures to weapons. Even the Sentinel robotic drones possess small holographic Forerunner script around their "eyes".

Forerunner Stellar Engineering
While the Forerunners' architectural and technological prowess is legendary among the Covenant and UNSC, their masterpieces also extended to the fields of stellar engineering. At least two Forerunner sites, the Shield World Onyx, and the Ark, made use of suns where none should exist. The Shield World existed permanently in Slipspace, where solar systems outside of a Dyson Sphere cannot exist, and the Ark was located far outside of the galaxy where galactic material would have been insufficient to form the sun that illuminates the Ark. Whether these suns are artificially engineered or simply moved from another star system by the Forerunner is unknown: either would have been an enormous technological achievement.

The Ark is confirmed to be artificial, due to its unnatural "flower head" shape. It has been theorized to be an Alderson Disk. It is likewise unknown if these are the only stellar engineering achievements the Forerunners made; whether the systems that the Halo Installations orbit are artificial or native to that region of space; whether other Shield Worlds exist; and how the construction or movement of such large stellar bodies was accomplished.

Known Fortress Worlds


Installation 04

 * Control Room
 * The Silent Cartographer
 * Alpha Base
 * The Library
 * Flood Containment Facilities
 * Bridges

Installation 05

 * Control Room
 * The Library
 * Quarantine Zone
 * Sentinel Wall
 * The Temple
 * Flood Research Facilities
 * Relay Station
 * Sentinel Production Facility

Note: that Installation 04, 05 and the Ark are the only three Fortress Worlds that have been directly observed in the Halo Universe.

Other Forerunner Structures

 * Installation 00 - Known as the Ark.Controls all other installations.
 * Gas Mine – Houses laboratories created to study The Flood.
 * Coral Facility
 * Onyx - An artificial UNSC controlled world, inhabited by, and made out of, sentinels.
 * Shield World
 * Backwash
 * Relic
 * Ark Portal

Forerunner Constructs

 * Monitors/Oracles - Floating A.I.s responsible for maintenance of Halo worlds and to make sure that the Flood stay imprisoned.
 * Enforcers - Enforce the Monitor's will. They are large, floating machines designed to serve to contain major Flood outbreaks.
 * Onyx Sentinels - Powerful, adaptive Sentinels guarding Onyx.
 * Sentinel Majors - An upgraded, much more powerful Sentinel.
 * Sentinels - Controlled by the monitors, they are responsible for guarding a Halo.
 * Automated Turret - Created to be a deployable equipment for the Forerunner to defend themselves against possible Flood threats or another type of threat.
 * Constructors - Small constructing devices that repair damage to any Forerunner structure they find, as they are responsible for the repair of a Halo Installation. They also act as a mobile patrol and security alarm units, seeing as how the Sentinels will come to their aid if they are attacked.

Forerunner Artifacts and Technology
See also Technology


 * The Forerunner Dreadnought
 * The Crystal
 * Deep-Space Artifact
 * Forerunner Hand
 * Forerunner Body Armor
 * Terminals

Known Forerunner Worlds

 * LP 656-38 e
 * CE-10-2165-d
 * DM-3-1123 b
 * G617g

Forerunner Glyphs and Symbols
Forerunner Numbers:

Found in the Halo 3 Iris servers, these symbols are possibly part of a Forerunner numbering system.

Forerunner Glyphs:

Some images of all the forerunner glyphs found spread all over the Halo Universe.

Iris Icon: An image of the Iris Forerunner icon.

Bases Signals
In Halo: Combat Evolved, in the multiplayer maps Blood Gulch, Longest, and Hang 'Em High, the bases bear Forerunner Glyphs; one red and other blue respective to the base color. In these maps are the same Glyphs for the bases.

Weapons
If you look closely at both the energy sword, plasma grenade and Sentinel Beams in theater, you'll see glyphs on the edges.

Campaign
In Halo: Combat Evolved, in the campaign level 343 Guilty Spark, Forerunner Glyphs can be seen on a few walls that have doors on them within the Flood Containment Facility. They can also be seen on the back of some Elites.

Multiplayer Characters
In Halo 3, on an Elite's armor near their wrists, you can see three Forerunner Glyphs. A Glyph can also be found on top of the Monitor in Forge Mode.

Forerunner in Covenant Religion
The Covenant venerate the Forerunners as gods, believing that the Halo Array elevated the Forerunner to godhood instead of killing them. As such, they have appropriated many Forerunner technologies and artifacts, and dedicated a significant amount of time to the search for other "holy relics" such as the Halo Installations, believing that they can follow the Forerunners into godhood. This is referred to as the "Great Journey" by the Covenant races. The Covenant believe that the Forerunner's ascension to god-hood was finalized after the rings were fired. They also appear to think that monitors are worthless as said by the Prophet of Regret, "they know nothing of the Great Journey!

Trivia

 * The Librarian and Didact are the only specified Forerunners in the known Halo Universe. They are mentioned in the terminals in Halo 3 as D: and L:.
 * The term Forerunner means "one that goes before". Latin for Forerunner is Precursor, which, ironically is the given name of the race that the Forerunner revere (as stated in the Bestiarum).
 * Only appearing in Halo:Combat Evolved, the Forerunner Symbols seemed to be present at the back of Zealots, SpecOps Elites and Stealth Elites. It is unknown why it is absent in Halo 2 and Halo 3. The Forerunners were speculated to be related to the Elites because of their glyphs that appear on their backs in Halo:Combat Evolved.
 * Many speculated that the Forerunners resembled humans. They show some similarities (their highly advanced technology and the fact that they mysteriously vanished) to the Jjaro, a race of aliens from a previous Bungie game, Marathon, the Eloh from the MMORPG Tabula Rasa, the Protheans in Mass Effect, the Precursors of  Star Control, the Rakatan or Builders of Star Wars, the  Progenitors of Homeworld, the Chozo of Metroid, the Ancients of the Stargate television series, and the Great Beings of Bionicle. The concept of a highly advanced extinct race leaving technological relics behind is not a new concept and has appeared in several other media such as books and films.
 * The Forerunner also bear a striking similarity to Larry Niven's Pak Protectors (Ringworld Series), whom also built a Ring-like Station but disappeared, leaving the Ringworld to go off balance from its own sun. It has long been speculated that Larry Niven's Ringworld Series inspired Halo's setting, Halo.
 * The very first ideas and concepts on Forerunner structures and technology was that it would be sleek and curved to give it an advanced feel. However Bungie wanted the structures to feel as if they could stand the test of time and redesigned them to be solid and monolithic. The smooth, near-organic design would later be adopted by the Covenant in their architecture.
 * Covenant Luminaries (actually stolen Forerunner equipment designed to detect other Forerunner objects) can detect humans, previously mislabeled as "Forerunner Artifacts", leading to initial Human-Covenant contact.
 * Engineers are the only known Forerunner creation to not be robotic and to join the Covenant.
 * Forerunners have the technology to encode DNA/RNA/silicon samples into data stream, and reproduce entire individuals from it. This was mentioned in the Bestiarum: "DNA/RNA/Silicon samples are encoded in this data stream. Reproduction of individuals for analysis is prohibited by this facility."
 * The Guardians are thought to be somehow related to Forerunners.