Flood (Halo)

File:Floodforms library.jpg

Halo's Master Chief encounters various flood forms in the Alpha Halo library.

The Flood is a fictional alien parasitic life form in the Halo video game series. They are introduced in Halo: Combat Evolved as a secondary enemy to the game's protagonist, Master Chief, and returned in Halo 2. They are depicted as highly virulent and deadly, and can quickly incapacitate and infect their vectors. The Flood have appeared in three primary forms: Infection, Combat, and Carrier forms, but also have forms such as the Brain form and the Juggernaut form which have not been fully explained or documented. All of these have an attraction to any lifeform of sufficient mass to accommodate them and will try to attack/infect any they encounter.

Flood first made their appearance in Halo: Combat Evolved's sixth level, "343 Guilty Spark". After reaching Halo's control room in the previous mission, Master Chief is sent by the AI Cortana to try and stop Captain Jacob Keyes and his UNSC Marines from reaching a weapons cache they believed was hidden in a Forerunner structure by a swamp. In reality, the cache was false intelligence; Instead of finding weapons, Keyes found that a sizable population of Flood was released from stasis by the Covenant. The Flood quickly escape containment and spread across the ring, threatening not only the Humans and Covenant, but the entire galaxy should they have escaped.

Overview

Life Cycle

In the game, the lifecycle of the Flood begins at the Infection form stage, as a small, frail, gas-bloated creature. These creatures leap upon a host and attempt to drive in three barbed tentacles (although the small spores that some Flood are seen to release are also used to either infect or incapacitate potential hosts, as 343 Guilty Spark explains over in the level "The Library"). From here, the host is paralyzed and loses consciousness. The infection form bores itself deep into its host. For a while it plays with its new body, and over time it mutates it by changing hormones and replacing the host's nervous system with its own tentacles. The host is still conscious as it is being controlled, but is confined to its own mind. However, if a host is infected by a Flood infection form with its ability to enslave the host weakened (Private Wallace A. Jenkins encountered this rare dysfunction in the novel Halo: The Flood), it may be able to reassert some control over its badly mutated and damaged body, provided the Flood host retreats from the host's mind temporarily. Also, if a host has sufficient will power (i.e. Captain Jacob Keyes), the host can fight against the Flood's invasion of their mind, and keep it from gaining access to certain parts of the mind (In the case of Capt. Keyes, he was able to keep the Flood from invading the part of his mind containing information about Earth). In the video games, the host is seen carelessly treated, with infected limbs, rotting organs, and the neck of the host broken. The disused head of the victim can be destroyed without causing the Flood form pause, and hordes of Flood will attack the player without regard to casualties. If the host is of suitable size, long whip-like tentacles emerge from the arms as weapons. If not of suitable size or sufficiently damaged to prevent use in combat the next stage of mutation occurs. The body becomes bloated and rotten. Smaller Infection forms grow within the ball of flesh, as it swells with gas and diseased innards. When the Carrier Form detects a suitable host, they explode, releasing Infection forms to continue the cycle.

Origins

See also: Forerunners (Halo)

The origin of the Flood has never been fully explained by the Halo games or books, their history lost in the time passed since their inception and their discovery in Halo. 343 Guilty Spark mentions that the Flood actually terraform the atmosphere to suit them: This hints that the Flood originally live or lived in an environment noxious to most other living creatures. According to what the AI character Cortana discovers during Halo, the Forerunner constructed research facilities situated over gas giants and later huge "Fortress World" installations (called "Halos" by the Covenant) to contain and study the Flood. In the event that the Flood was released and all other strategic possibilities were exhausted, the Halos were designed to destroy all sentient life in the galaxy; In Halo 2 the character Guilty Spark states that the Halo system was fired at least once, killing all life—including the Forerunners—as planned. The thinking behind this is that if the Flood has no food then it will eventually starve to death, allowing the galaxy to slowly re-populate and preventing the Flood from spreading to even more galaxies throughout the Universe. Despite this measure, some Flood survived over the years and were later released during the events of Halo: Combat Evolved.

Game Development

The Flood were added later in the game development stage of Halo: Combat Evolved, after the game had made its jump from the Macintosh platform and Bungie was bought by Microsoft. At one point, the ringworld Halo featured dinosaur-like terrestrial creatures, but due to gameplay constraints, these were dropped. An additional consideration was that Bungie felt the presence of other native species would dilute the impact and surprise of the Flood.

Flood forms

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Infection form

Infection forms

The infection forms are small creatures which use tentacles for mobility and infection. They appear to have their own defined biological framework, as in the games they are seen without a host and do not appear to need one to survive. Individually they are weak and fragile; in the game they usually appear in huge swarms. The infection forms will seek out any sentient life of capable bio-mass and calcium deposits to sustain itself, and proceed to attempt to use the creature as a host, by tapping into the spinal/nervous system, suppressing the host's consciousness, embedding itself in the thoracic cavity, and releasing spores which cause the host to mutate. (343 Guilty Spark mentions these "spores" during his own synopsis of the Flood life-cycle.) At this point, the infected creature mutates into a possible one of three other forms.

The infection form parasites attack in a swarm that rapidly advances on host organisms, then physically attach themselves to a host as they try to burrow into its chest. If not quickly removed, the organism will begin to modify the host's genetic code and take over. In the games, the infection form cannot attach to a host if the host is protected by a personal energy shield; contact with the shield will make them explode with a distinct "pop" sound and will have a minimal effect on the shield's strength. However, if several dozen try to attack a shielded host they will gradually deplete their shields to the point that they are vulnerable. Thus, soldiers such as the human SPARTAN soldiers and the Covenant Elites have some protection against the Flood and may mount a counter-attack, but unshielded troops (the majority of both armies) such as UNSC Marines and Covenant Grunts, Jackals Brutes, and Drones are highly susceptible to an attack by masses of infection forms. Brutes have not been seen infected, while the symbiotic communal nature of the Hunter makes them immune to infection.

Combat forms

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Human Combat form

If the host is strong or deemed "useful" by the parasitic infection form, then the host will be converted into a warrior or worker form, used in defensive/offensive situations as well as maintaining and repairing machinery. In Halo 2, the Flood have the ability to pilot and repair vehicles, which suggests that the Flood utilize the memories and knowledge of their hosts. The Halo novels also make reference to the Flood leeching the memories of their hosts to use equipment. These warrior or combat forms are extremely strong and agile and can jump to extreme distances and heights, with the Covenant Elite-derived combat forms sometimes being able to use the energy shielding technology on their remaining Elite armour in Halo 2, or the cloaking in the armory in the Maw level in Halo:Combat evolved. However, the parasite form within the host is susceptible to gunfire and, if shot, completely disables the combat form until another infection form burrows into it and takes control. These forms can use all UNSC and Covenant weaponry, but are not seen using the Fuel Rod Gun (and in Halo they did not use sniper rifles). Combat Flood are also capable of unarmed combat, striking with whip-like tentacles protruding from the arms of the host. These tentacles can grow out of the arm at an alarming rate, simply breaking the nearby bones and displacing them. They also carry the grenades equipped before the host was infected, which are dropped when killed. Flood combat forms ignore any threat to themselves and those fighting alongside them and will often kill themselves to kill an opponent. The source of this reckless behaviour has never been identified, though because the Flood are intelligent—albeit not necessarily on an individual level—it is unlikely that the explanation for the wantonly violent ways of combat forms is quite as simple as a primitive drive to obtain food.

Carrier forms

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Carrier Form

The third stage of the flood cycle. A combat form mutates into a carrier form when it is horribly damaged or useless in battle. Carriers grow large sacs which contain several infection forms. When a carrier is in close proximity to any number of suitable hosts; or is fired upon it triggers some manner of biochemical reaction, causing the sacs to explode and spread the infection forms in order to infect more hosts. This continues the Flood life cycle. Also, as the Flood do not care for their physical forms, older and worn combat forms can be turned into carriers once they have outlived their usefulness. Covenant Grunts, Jackals, and decayed combat forms are often used to serve as carrier forms.

Brain forms

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Captain Keyes, mutated into a Brain Form

Brain forms are large, spongy Flood forms which resemble a large bag of flesh with tentacles. They are seen used in Halo: The Flood to collect information on important things, such as codes, planet locations and information about the species that the Flood can infect. In Halo, Captain Jacob Keyes was subjected to an 'interrogation' of sorts by one of these forms before finally being assimilated by the Flood form.

Over time the Brain form strips memories and information from its victims. However, Keyes was able to resist giving the Flood information regarding the location of Earth when he realized that the Flood could not strip away information that he could draw from his neural implants, such as his name, rank, serial number, and the name of the ship that he commanded. Thus by "feeding" the Flood that information, he could continue to access it and avoid giving the Flood more important information. All body tissues and bones are soon reduced to fluid, and is digested as the brain slowly absorbs the information.

Command forms

The command forms, due to their limited exposure in the Halo trilogy, are not well understood. Their purpose is not exactly known. The Gravemind from Halo 2 is a command form over either all Flood or that on Installation 05 (Delta Halo). When the Flood invaded a Covenant supply ship in the story Last Voyages of the Infinite Succor they used corpses and dead biomatter to feed what appeared to be a much smaller, developing gravemind, which the Prophet Legate assumed to be a sort of central brain controlling the infestation.

Flood details

It appears that the Flood cannot or will not infect already dead lifeforms, as one of the Marines in Halo evades the Flood by playing dead. However the ability of infection forms to reanimate incapacitated Flood forms seems to suggest that once the initial infection has occurred, a new Infection form can quickly take control. The Flood have been noted to gather corpses for use in the construction of command forms, however.

The Flood on Installation 04 were destroyed in due to the player's actions in Halo: Combat Evolved, but in Halo 2 they returned, with the ability to operate in-game vehicles. In Halo 2, the Flood are led by the command form Gravemind, a massive creature that dwells beneath Delta Halo's Library and on High Charity. It is not currently known if there is a Gravemind in each Halo, or if the Gravemind encountered on Delta Halo is unique.

External links

• Halopedia - Halo Knowledge center
• Bungie.org Flood Archives
• Flood Discussion @ Bungie Forums