The Flood (Latin Inferi redivivus meaning "The dead reincarnated" or The Parasite, as they are known to the Covenant), are a species of highly virulent parasitic organisms that reproduce and grow by consuming sentient life forms of sufficient biomass and cognitive capability. The Flood was responsible for consuming most of the sentient life in the galaxy, notably the Forerunners, during the 300-year-long Forerunner-Flood War. The Flood presents the most variable faction in the trilogy, as it can infect and mutate Humans and Covenant species, such as Sangheili, and Jiralhanae, into Combat Forms. They are widely considered to be the greatest threat to the existence of life, or, more accurately, biodiversity, in the Milky Way galaxy.
Variable, depending on host
Variable, depending on host
Variable, depending on host
Significant Physiological and psychological mutations. They can also acquire their host's memories
Equipment used by it's host prior to infection
Gravemind, Captain Keyes, Timeless One, Wallave A. Jenkins, High Prophet of Regret
Flood, Parasite, Stellar Disease, Unforgiving Wrath
Precursor Civil WarEdit
During the Precursor Civil War, the Elder faction knew that they were rapidly losing their war with the stronger Eternals, and knew that a continegency plan was needed. After alliance's with Humanity and the Forerunner failed, the Elders decided to bypass the laws of the Mantle and create a bioweapon to eradicate the Eternals, allowing to appeal directly to their leadership.
After testing over Trisca, originally a Elder-occupied Precursor colony, the Flood effectively became a biological superweapon that the Elders could use to create quick and easy shock troops. However the Flood became much too intelligent, and after a quarantine breach, the Flood infected the Elder science flotilla orbiting Trisca, and crashed into the planet. Seeing the Flood as a failed experiment, and that wasting troops and resources to deal with the parasite would be too cost prohibitive, the Elders deployed a later strain called the Malidasium, deploying it on Trisca and giving it a single goal: destroy the Flood.
The Infected Wars enveloped the whole planet, with the Flood taking massive defeats worldwide. Using their own tactics against them, the Flood stood no chance against the Malidasium. Losing hosts to infect and control, the Gravemind became desperate and tried to find a way to wipe out the Malidasium.
After the Flood discovered that the Elders were keeping a constant supply run of hosts to the Malidasium (which turned out to be Eternal prisoners), the Gravemind launched an assault against a docked Precursor frigate. Hijacking the vessel, and soon the entire Elder battlegroup above the planet, the Flood used the Devastator Cannon to glass the planet, not only destroying the planet's biosphere and vaporizing the planet's atmosphere, but wiping out the Malidasium.
After infecting Precursor recon ships sent to investigate the battlegroup's disappearence (as the civil war had ended), they plotted a course straight for Zeban. However, thanks to the Timeless One's personal task group of Elysium-Class Cruiser-Carriers spotted the ships and classified as hostile, the Precursor Fleets entered attack formation over Zeban.
This naval blockade stopped the Flood, but nevertheless initiated all out war. This war lasted a considerable amount of time, but by the time the Precursors had cleansed every colony of the parasitic menace, the Flood had already been defeated. Forced into exile, the Flood were chased out of the galaxy, and the remnants of their infected hosts rounded up and burned, to stop the risk of contamination. Trisca had adapted to the flood presence and was officially labelled the Flood's homeworld.
The Flood eventually returned and started infecting Human colonies shortly after the conclusion of the Precursor-Forerunner War. They rapidly began infecting human and San'Shyuum colonies, and by the time the infection was discovered, half of the empire's colonies had been overrun. Passing down the law that all Pheru, popular galactic pets who had served as Flood carriers, were to be exterminated, the Empire and the San'Shyuum began a war of cleansing against the Flood.
With a overwhelming population, the Flood completed their goal of forcing humanity to aggressively conquer Forerunner colonies to stabilize their own populace. This lead to war between Humanity and the Forerunners, however by this time, Humanity had discovered a cure for the Flood disease, and had dispersed. Forced to escape extinction, the Flood once again went into exile, leaving the galaxy, but leaving the galaxy in a state of conflict.
The Halo ArrayEdit
Wanting revenge for the extinction of his race, the Timeless One, now consumed by the Flood and turned into a Gravemind, made a secret deal with the deevolved humanity to unleash the Flood upon the Forerunners. After destroying their cure, the Timeless One once again unleashed the flood upon the galaxy. It wasn't long before the Flood began to slowly overrun Forerunner colonies, and with no experience on how to combat infection, the Forerunners were forced to slowly keep retreating and retreating.
Desperate to save all galactic life, the Didact devised a plan to starve the Flood of their food. Using Shield Worlds, all life would be stored in sanctuaries and cut off from their food, the Flood would starve to death. The Shield Worlds were completed and deployed, with 50 in total, but the plan proved to be too costly and too time prohibitive. Instead, the Halo Array was developed as a last resort measure. It became last resort when Mendicant Bias, a rogue Forerunner AI, deliberately joined the Flood and lead a massive flood infected fleet to attack the Maginot Line, the Forerunner's last fortress.
With all hope of defeating the Flood conventionally gone, the Forerunners activated the Halo Array, wiping out all life in the galaxy, with data files containing the DNA of the many species wiped out, catalougued on the Halos so that life could reseed. With the Flood defeated, the Forerunners decided it wise to put the surviving Flood in containment facilities on the arrays, so a to learn more about them.
Galactic Safety Once Again JeopardizedEdit
For hundreds of thousands of years, the Flood remained contained as the respective Forerunner AI researched them, trying to find a cure. Years later, the Covenant discovered Installation 04 and accidentally released the parasitic menace, mistaking the containment facilities for a Forerunner weapons cache. Released, the Flood began to infect all humans and Covenant alike, quickly spreading all over the ring.
The Covenant attempted to escape, but the Flood spreading was underestimated. The Flood eventually managed to infect the whole ring, and in an attempt to escape the ring and begin their galactic infestation once again, began rebuilding the downed human vessel, Pillar of Autumn. However, thanks to John-117, the ship was destroyed, and along with it, the ring. The Flood their were thought eliminated, but later the Flood managed to escape containment on Installation 05, and a few months later, that ring was discovered by the Covenant and the UNSC. This ring was also shutdown, but the Flood managed to infect High Charity, the Covenant capital and set it on a course for Earth, which had lately been devastated by a Covenant Loyalist counterattack.
Fearing the Flood's intention was too infect Earth, the UNSC prepared for a final stand, but this proved not to be the case. Instead they used the portal found in Voi to reach Installation 00 or the "Ark," so that they could destroy the Halo Array. However, thanks once again to John-117 and the Arbiter, the Ark was destroyed and with it the Flood. This caused the rest of the rings to go into self-destruction, save Installation 03 and Installation 07, which for reasons unknown, became disconnected from the Halo network. With the Halo Array destroyed, the Flood were thought finished.
Later in the Second War, and even later in the Second Human-Sangheili War, the Flood were encountered on Installations 07 and 03. However, these installations were also destroyed, which brought a final end to the Flood, confirming the race to be extinct.
BiologyEditThe Flood, a virulent species of parasites, is an anomaly in all known biology, and an anomaly to regular life. This may be explained by its nature as an extragalactic species, originating from a different galaxy. It is extremely adaptive, and mutates hosts through different stages of accelerated "evolution", where the body of biomatter accelerates its own evolution to the point of a massive biological breakdown, where by the infection can first take place. The species can reproduce without host bodies, though this is described as a last ditch effort, and only performed by pure Flood forms.
The only known pathway for Flood reproduction and survival is by the infestation and assimilation of other species. They do this through a form of cellular reproduction known as lysogenic replication where the viral cells infect host cells with their own genetic code which mutates the host cells into viral forms.
Capable of surviving extreme environments ranging from -75 to +53 degrees Celsius and even underwater (in early stages of life), the Flood can withstand harsh environments of all known colonized planets.It would seem that the Flood can infest any living organism, but that they prefer hosts with a large brain capacity to accelerate the formation and expansion of the Gravemind hive intelligence and the Flood intelligence as a whole. They are only as intelligent as the beings they infect; the more cunning the enemy, the more dangerous the Flood will be.
As the Flood spread and replicate, they will alter the environment to better suit their needs. This takes the form of biomass growing on any available surface, and the air being filled with spores. This appears to be part of the Flood life cycle and is done automatically, and leads to the development of a Gravemind and a Flood Hive.
The Flood seem to thrive in moist and humid areas, which lends itself to the fact that the Quarantine Zone is bereft of organic life, and is cold and perpetually snowy, to hinder the development of the Flood.
Infection forms selectively target other species that possess sentient intelligence and are of sufficient biomass, and can infest living or lightly wounded dead bodies. Infection forms have long tendrils that pierce the skin of the host and find their way to the spinal cord. From here they synchronize with the host, matching frequencies with the host's nervous system and killing them almost instantly. From there, they take control of the host body, replacing whatever mind originally resided there with the ravenous and voracious psyche of the Flood, although certain higher-level cognitive abilities, such as combat techniques and technical knowledge which may be useful are retained, scanned from the victim's brain after death. Despite this lingering of certain memories, no trace of the original mind's personality remains; only a simplistic and primal urge to assimilate or destroy other species drives the organism after infection. In isolated cases, such as when the Flood seek very specific information from an individual's mind, they utilize an alternate, undescribed method of infestation that does not kill the host immediately; this allows the Flood to "burrow" into the host's mind, eventually giving them access to the entire scope of the host's memories. This has only been specifically seen when the Flood sought information from Captain Jacob Keyes, such as the location of Earth or a starship that would free them from Installation 04. In addition, if the Infection Form that initiates assimilation is extremely aged or damaged somehow, the death of the host can be removed from the equation entirely; Private Wallace Jenkins suffered such a fate, remaining alive and fully aware of his situation despite the mutation of his body, even exhibiting limited control over his body at times when the Flood instincts were dormant.
If a greater Flood intelligence, such as a Gravemind, is activated, then it is capable of overriding the primitive instincts of all other Flood forms, taking direct control of each and every Flood organism and making them much more dangerous as a result of being guided by a sentient mind. It is unknown what would have happened to a still-living host such as Private Jenkins when a Gravemind attempted to influence control over it, as no living hosts were ever encountered after the activation of a Gravemind. In addition to controlling the physical movements of the host body, the Gravemind can utilize the vocal cords of combat forms made from former Jiralhanae, Humans, and Sangheili to communicate, as well as the moans they use as observed on The Covenant where the drop pod crashes into the third shield tower.
While baseline neurological assimilation is the same regardless of host species, The Flood's infestation includes physiological mutilation, which is species-specific.
Higher-level species capable of combat, such as Humans, Jiralhanae, or Sangheili are selectively infected to become Combat Forms. Combat Forms retain the general profile of their original species, although they are significantly mutated. Organ-based systems' physiology are corrupted, organ-specific functions are decentralized, and body cavities are decayed, making hitbox-selective incapacitation impossible; organ functions are decentralized, thus, decapitation does not down a combat form. Furthermore, highly area-specific munitions, such as sniper rifle projectiles, are completely ineffective, as picking off selective areas of a combat form leads to no wide-scale physiological impediments, and the projectile will punch through the decayed flesh rapidly, exiting through the other side of the combat form without consequence.
Combat forms also generate tentacles very quickly without regard for the skeletal structure of the host, with tentacles protruding from the combat form at odd locations, typically localized to the chest axial regions, such as the neck, armpits, or torso. A single arm is oftentimes mutated to a claw like or tentacle-like structure that splits into multiple angular, hand-like structures replacing the hand's usage, yet it will still be there. The musculature of the combat form dramatically changes as well, and the form is given prodigious arm and leg strength, allowing for heavy blows with its arm-like structures and for incredible speed and jumping height with its legs. The Flood are also prodigious climbers, able to scamper on walls with little hindrance to the organism . Metabolic requirements, however, appear to be extreme on the organism: blood vessels become extremely prominent on the surface of the Combat Form, with thick and distinct blood-colored vessels spawning all across the creature's surface, most prominently so on the head.
CountermeasuresEditThere is no confirmed way to effectively stop a Flood infection when an Infection Form attacks a host. However, two possible exceptions are known. One of which is to contract the disease "Boren's syndrome", a neurological condition where radiological exposure causes electrical anomalies in the host nervous system, similar to some of the effects caused by several biologically enhancing drugs used in the ORION Project, the precursor to the SPARTAN Program . In the case of both neural frequencies of the host are scrambled, apparently without major negative manifestations to the host. However, it has been suggested that during Flood infection, the infection form is unable to tap into the host's nervous system to kill and consequently infect them; therefore unable to proceed to a large-scale physiological mutation, although Flood DNA is sliced into host's DNA, apparently imparting the host with increased regenerative capabilities, although this has not been independently verified. Avery J. Johnson, having Boren's syndrome, escaped the containment facility where The Flood attacked two squads of UNSC Marines. However the Boren's syndrome was a story invented to cover his past in the ORION Project and the side-effects of his (experimental) enhancements, so the validity of each as a countermeasure against Flood infection is questionable. In the novel Halo: The Flood, Cortana uses an electrical charge which she generates from Master Chief's suit to destroy an infection form that was attempting to infect him.
While Boren's syndrome left untreated may leave the victim immune to the Flood, leaving it untreated usually equates to death within a couple of years. There is said to be a one in a billion chance that research, from someone so inflicted with Boren's syndrome in a way that they cannot be infected, could be carried on to produce a cure.
Since the Flood is a parasitic life form, they depend on other organisms for survival. Thus, the only logical foolproof way to eliminate them permanently is to take away their food sources. The Forerunners attempted this by bombing large population centers, but this was seen as one of their last resorts and as such was performed too late in the war to make much difference. The absolute last resort was the use of the Halo installations, which effectively destroyed all life in the galaxy and starved the Flood into extinction. However, the Forerunners' plan included some measures to preserve sentient life and return them to their home planets, allowing the Flood's "food source" to persist. Unfortunately, at the same time, specimens of Flood spore cells were kept for analysis on the Halo Installations, allowing the threat of the Flood to be merely forestalled, not eradicated.
Environmental stimuli seem to have an effect on Flood metabolism. Halo installations typically artificially incorporate low temperature into environments suffering Flood outbreak and to create natural obstacles to Flood progress, regarded as Quarantine zones. At least one Flood Research Facility used low temperatures to keep its specimens inactive and dormant as it studied them.This may be the reasoning behind keeping Installation Control Rooms in low degree weather, impeding their occupation by the Flood. The Flood are also vulnerable to temperatures on the other end of the spectrum. Plasma weapons will burn through them, as well as Sentinel Beams, which were specially designed to counter the Flood, indicating that the Forerunners had determined energy weapons to be the best 'basic countermeasure' available to fight the Flood. It may be a side-effect of the Flood's conversion of the body into biomass, breaking down cellular integrity and increasing flammability.
The Flood go through four stages of development:
Feral stage is the lowest form, communicating via pheromones and have the natural instinct to harvest enough calcium to establish a viable Gravemind (Encountered in Halo: Combat Evolved and Halo Wars).
Coordinated stage is when the Flood become truly dangerous; they are now controlled by the Gravemind that was created in the first stage (Encountered in Halo 2).
Interstellar stage allows the Flood to take control of most technology and spread throughout the galaxy to infect more hosts (Encountered in Halo 3).
Intergalactic stage is the last known stage the Flood enters, theoretically, in which it utilizes all captured technology to depart to other uninfected galaxies to replicate. It is assumed the Flood never reached this stage, but during their many exiles, could of further infected other galaxies.
Universal stage is a theoretical stage in which the Flood fully consume all universal life, infecting every galaxy, system and planet. It is thought that by that stage, the Flood would begin to consume itself, as it has lost its main supply of food.
The most basic form of Flood evolution is the infection form, unique in its distinctive spherical shape. The infection form is used to infect organisms of other species, physically adhering to their surfaces and inserting tentacles, forcibly "hacking" into its host's nervous system, completely changing its psychology to that of the Flood's, and eventually physiologically mutating it into one of the various parasitic Flood forms of whatever the victim may be. The Elite combat form, may use the shield in the armor of the host. The Tanks form, is about the size of a hunter, and can release infection forms from its body. It can mutate into two different forms: Stalker form, and Ranged form.
|Known Flood Forms|
|Feral||Infection Form • Combat Form • Carrier Form|
|Pure||Stalker Form • Ranged Form • Tank Form|
|Advanced||Proto-Gravemind • Gravemind|
|Uncategorised||Flood growth pods • Flood dispersal pod • Porta • Flood Hive • Flood Spores • Flood Launcher • Flood Swarms • Flood Den • Bomber Form • Thrasher Form • Flood Stalk • Flood Vent • Flood Colony • Flood Root • Water Form|
Juggernaut • Shielded Carrier Form • Infector Form • Transport Form • Stealth Form
Combat BehaviourEditWhile possessing an unusual sentient intelligence, with Combat Forms still retaining extremely high-level cognitive functions such as vehicular operation, traits such as dexterity and complex battlefield tactics are notably lacking in the Flood, especially in their psychological and combat behavior. While the Gravemind coordinates Flood strategy on a galactic scale, small encounters are not coordinated between individual Flood warriors.
The Flood's strategy is simple: They throw themselves at potential hosts in huge numbers and with any and all weapons available. Flood tactics are based primarily on asymmetrical warfare: the Flood uses all types of its different forms to kill the enemies that it sees. Infection forms swarm across the battlefield in waves, reanimating any corpses they can find, while Combat forms attack and kill any hosts in sight. Pure forms, if present, provide support to Combat forms in a number of ways: Stalker forms move to strategic positions and mutate into either Tank or Ranged forms, which can destroy enemy vehicles or fortifications or provide suppressing fire from afar.
The Flood have a strong preference for close-range combat: combat forms possess abnormally strong melee attacks by whipping their tentacles, capable of lowering a SPARTAN-II MJOLNIR armour’s shields to half its original power with a single hit. Carrier forms cause tremendous devastation at close ranges, and their explosions are extremely devastating to friends and foes alike, with the added benefit of disseminating infection forms in the immediate vicinity of enemies. Infection forms are capable of attacking only at point-blank ranges, exploding in damaging bursts when meeting an opponent's personal energy shields or instantly grabbing hold of an unshielded enemy organism and infecting it. Combat forms can also use firearms, and have only ever been seen clutching them in one hand (regardless of whether it is one-handed or two-handed). However, combat forms struggle with ranged weaponry: it is believed that the neurological ramifications of Flood infection significantly decrease accuracy, as well as weapon recoil if held in only one hand. The Flood are, on the other hand, very effective with heavy weaponry such as the M19 Rocket Launcher or the M90 Shotgun, and are curiously ill skilled with close-quarters weapons such as the Energy Sword. However, it is still possible that a Flood with a Energy Sword can kill a fully shielded Elite or Spartan in one blow.
However, as mentioned previously, the Flood demonstrates a curious higher intelligence despite their poor combat aptitude and coordination. The Flood collectively learn any general information a species possess, even if only one member of that species is assimilated. For example, during the ill-fated raid on the Infinite Succor, after only one Sangheili was infected, the Flood could open any doors and access any system on the ship immediately afterwards, demonstrating that the Flood can share collective knowledge across their species. Furthermore, when the Flood assimilated the Prophet Legate, the Flood reflected the high-level knowledge of the Legate through its individual organisms to Special Operations Commander Rtas 'Vadumee, mocking him with the words, "the Forerunner could not defeat us...what chance you?". The Flood, however, reflect unusual knowledge in the individual psychologies of its individual species in processes facilitating increased infestation: The Flood were sighted gathering bodies in the corners of the Covenant ship Truth and Reconciliation, perhaps making it easier for Infection Forms to find hosts to reanimate. The Flood were also gathering body parts for a new Brain Form aboard the Infinite Succor.
Flood Combat forms have been sighted crudely operating Ghosts, Warthogs, Wraiths, and Scorpions in ground operations, although with slow deliberation and clumsy driving and accuracy. The assimilated crewmen of the UNSC frigate In Amber Clad were also able to initiate a Slipspace micro-jump for the frigate and perform rudimentary maneuvering of the In Amber Clad, navigating the frigate from the atmosphere of Delta Halo to High Charity and then crashing the vessel into a tower, releasing Pelican dropships to rain down upon the capital.The Flood's millennia of existence has made the assimilation process extremely brief: hosts killed in a short firefight can be reanimated within seconds to minutes by an infection form, and live creatures can be mutated into fully developed combat forms within the same time frame. Sometimes the rate of the mutations can vary in very rare cases: when Rtas 'Vadumee battled his comrade-turned-combat form Bero 'Kusovai aboard the Infinite Succor, 'Kusovai continued to mutate throughout the duration of the battle at a restrained and constant rate. Though never seen within the story, it can be assumed infection forms were involved in infecting a victim. Before being killed to prevent him becoming a Flood Combat Form, one of the Sangheili accompanying Rtas 'Vadumee has a wound in his chest that is consistent with the entry point for an infection form.
The Prophet of Truth in his final moments was infected by the Flood and began to mutate, but the rate and nature of his transformation was not consistent with the usual process when a sentient being is taken by a Flood Infection Form. It is likely that this was influenced by the nearby Gravemind, who was either controlling the Infection Form's activity, or controlling the mutation of the Flood spores within Truth's body.
- Minister of Etiology
- Wallace A. Jenkins
- Captain Jacob Keyes
- Sub-Commander Bero 'Kusovai
- Manuel Mendoza
- Eugene Yate
- High Prophet of Mercy
- Private Riley
- High Prophet of Regret
- High Prophet of Truth
- It is revealed in the Halo: Combat Evolved Anniversary terminals that the Flood's presence on the Halo rings and other installations is due to both the need to study them as well as the need to preserve them as a species.
- Part of the Flood's Binomial nomenclature, Inferi, is Latin for "The Dead", and could be a reference to Roman mythology, as this was their name for the Netherworld and it's inhabitants. Inferi means 'The Dead' and Redivivus means 'renovated, reconstructed, rebuilt or recycled' so literally Inferi redivivus means 'The Dead Reconstructed'.
- The Flood bear a strong visual resemblance to an enemy cut from Marathon 2, the “fungal zombie.” They were to be the result of a bioweapon invented in the final days of the ancient S'pht and reused by Robert Blake's forces on Lh'owon, designed specifically to target Pfhor. Both the fungal zombies and Flood were principally designed by Robert McLees.
- Every time a Combat Form (not any of the Pure Forms) dies, the infection form in the chest will disappear.
- There is a species of fungi that is frighteningly similar to the Flood, the Cordyceps unilateralis. They attack carpenter ants and take over their neural system in order to make the ants go to high places. By the time it gets there, it's been rotted from the inside out like a Flood host and it releases spores from that vantage point.
- In a PC World article, the Flood was voted as #31 of the top 47 "most diabolical video game villains of all time."
- The Flood were inspired by Christopher Rowley's The Vang, though they bear some similarities to The Borg from the Star Trek universe.
- Their similarities wth the Borg include a single guiding intelligence (the Borg Queen and the Gravemind), the desire to achieve perfection and the need to assimilate/infect others into their society.
- In Halo: The Flood, Master Chief was attacked by an Infection Form while his shields were low. The Infection Form had slit the under parts of his armor, exposing his neck, and almost tapped his spinal cord. If not for the quick use of an electrical shock by Cortana to kill the form, Spartan-117 would have been infected like many before him.
- The name "The Flood" is a reference to the biblical story about the Great Flood in which God destroyed all life except for that which was carried by Noah's Ark.
- In Halo 2, Combat Forms will go berserk if you kill their allies near them. They drop their weapon and charge at the nearest enemy.
- The two species, Huragok and Yanme`e were never seen infected.It is unknown if Bungie ever planned the two to be infected by Flood.Even through modding, it is impossible to make Huragok and Yanme`e Flood (Combat forms).
- In Origins, during the scenes in which the Flood attacks the Forerunner planet, there appear to be many types of Flood, from very large, near-Gravemind-like ones that could level buildings, to flying versions of Infection Forms. In addition, some of the variations seen in Origins are based on concept art for the original game.
- Also in Origins, one of the large forms appears to "eat" a Forerunner. It is likely trying to absorb biomass and/or knowledge.
- Sergeant Avery J. Johnson is the only known human to survive a direct assault by an Infection Form without aid. This is due to the fact he is a member of ORION and his genetic makeup is different than that of a regular human being.
- The Flood seems to be the reason for the "Gore" label on the Mature rating. In all three games of the Halo trilogy, it is rated for "Blood and Gore", but in Halo 3: ODST, which uses the exact engine of Halo 3, it is only labeled for having "blood", as the Flood are one of the only absent enemies. The same occurs with Halo: Reach.
- The Flood was named #45 on IGN's Top 100 Videogame Villains list.
- The Flood can actually use active camo, but only Flood Elites have been seen using it. They are located in the Pillar of Autumn's armory.
- It is possible in Halo: CE to shoot the majority of a human Flood form's face off, leaving only its teeth and chin. In Halo 3, this will leave a large, red-rimmed black spot on its face. This is visible using bump possession cheats or theater mode, respectively.
- In Halo: Combat Evolved Anniversary, it is worth noting that the game models of the Flood are those of Halo 3 whereas their behavior, sounds and reactions to weapons are those of the original Halo: Combat Evolved. It seems that newer models were not made to make the Flood appear as if the newer Elites had been infected. This sets them apart from the Elite models in the game.
- Many mutations of the flood that are performed on organisms looks much like the alien transformations from the 1982 film John Carpenters The Thing, being that they are mutated into organisms of hatred and evil, as well as how the body, or host, is manipulated, even how it can possess the host's memories, only that the Flood do not create a virtually perfect imitation
- The Flood are one of the two species not to appear in Halo: Reach.
- In one of the terminals in Halo: Combat Evolved Anniversary, 343 Guilty Spark speaks about the flood.
- In Halo 3, it is noted that the Infection Form infects the human or Elite "alive". However, if you look more closely, the host body cracks their neck, as a result, the Infection Form actually infects the host when they are dead. This means that the Infection Form taps into the neural nerves before it actually infects the body.
- At SDCC 2012, 343 Industries informed the public that the Flood will not be making an appearance in Halo 4.
- It was confirmed as of 2600, the Flood had been completely eradicated.
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