300px-Halo 4 visual render 3

Unggoy (Monachus frigus)


Biological information


Physical description
Average height:

4 ft 


54 kg (118.8 lbs) 

Skin color:

Mottled gray/brown


Short, stocky, round head, exoskeleton with wrinkly skin, high-pitched voice, stubby limbs.

Military and political information
  • Unggoy combat harness
  • Methane tank
  • Special Operations
  • Heavy
  • Ultra
  • Major
  • Minor
  • Deacon

The Covenant, Heretics, Covenant Separatists

Notable individuals:
  • Dadab
  • Yayap
  • Flipyap
  • Yapflip
Other nomenclature:
  • Grunt
  • Chimp
  • Crab
  • Monkey
  • Gas-sucker
  • Crybaby
"When in doubt, flee"
— Unggoy philosophy

The Unggoy (Latin: Monachus frigus, meaning "cold monk") is a species of squat bipedal vertabrates in the unified races of the Covenant. They are the lowest-ranking species in the hierarchy, and are frequently mistreated by almost every higher-ranking race. Unggoy are primarily used as laborers, slaves, or, in combat situations, cannon fodder. They are one of the later races to be introduced into the Covenant, and were either the second or third Covenant species to be encountered by Humans . They are referred to as Grunts by humans, mainly because they are considered weak compared to their superiors, and also because they perform the majority of the physical labor required by the Covenant and they do not have much knowledge compared to other covenant species.


The Ark and reseedingEdit

Prior to the activation of the Halo Array, the Unggoy had managed to achieve a Tier 6 society on their homeworld, Balaho. However, the planet and the Unggoy civilization was devastated by the collapse of its biosphere due to massive global overindustrialization.

The Unggoy were one of many species indexed by the Librarian for preservation on Installation 00 from the firing of the Halo Array. They were subsequently returned to their homeworld Balaho, where they began re-building their culture.

Introduction into the CovenantEdit

Grunts were the sixth client race to be integrated into the Covenant, not including San 'Shyuum and Sangheili, about 411 years before the end of the Human-Covenant war, roughly coming to their indoctrination in 2142 on the military calendar. By the time of their discovery by the Covenant, the Unggoy homeworld was still recovering from its ecological collapse over a hundred millennia earlier, and the Unggoy civilization had yet to return to it's former state.

While they are essentially a slave race, the Unggoy have managed to largely retain their cultural identities, and have rebelled in the past several times. Being the lowest-ranked species of the Covenant, they are bitter rivals with the Kig-Yar, who are also low-ranked. The higher-ranking races of the Covenant have often ignored this rivalry. The breaking point came when a junior staffer in the Ministry of Concert discovered evidence of the Kig-Yar planning to poison recreational narcotics the Unggoy enjoyed, which would have left them sterile, but the High Council refused to investigate the matter. The rising tensions with the Kig-Yar and the general disinterest from the other Covenant races led to an Unggoy Rebellion in 2462. While the rebellion was ultimately put down thanks to an Arbiter and the near-glassing of the Unggoy homeworld, the Unggoy proved that they were not the cowards they had been long deemed, and could indeed be vicious fighters when provoked. After the uprising's conclusion, as was their tradition, the Sangheili forgave the surviving Unggoy and allowed them to enter the Covenant military as armed infantry units, rather than the unarmed cannon fodder as which they had previously served.

Despite the low place they have in the Covenant Hierarchy, the true irony is that the Unggoy's entry into the Covenant has ensured their species' survival. Membership in the Covenant granted the Unggoy freedom from risk of extinction during Balaho's two winters, as they now have access to sufficient supplies of food. Infant mortality has decreased to below fifty percent, and geronticide is no longer a necessity for survival. The average life expectancy for non-combatant Unggoy has doubled. Their incorporation into the Covenant likely also alleviated the threat of the Blue Death, which Unggoy typically fear.

The Great SchismEdit

The Unggoy obey other Covenant races out of fear more than religious faith. They have next to no political power in the Covenant; the highest political rank available to an Unggoy is Deacon. Within the Unggoy community there is a strong resentment of other species, especially the Kig-Yar. The low rank of the Unggoy, as well as the aforementioned war, also led to a lack of political loyalty during the Great Schism, as the Unggoy did not ally with a particular side, and stayed with whoever commanded them, most likely out of subservient fear to their current masters. However, many of those serving under the Jiralhanae still held support for the Sangheili and revered the Arbiter, pointing out to their comrades that they once served under him.


Unggoy are typically poor warriors in terms of skill, poor shots when not focused, physically weak, and are generally on the whole, quite tactically inept. When witnessing their commanders eliminated during a battle, they often go into a panic and scatter in random directions. However, what Unggoy may lack in individual skill, they make up for with sheer numbers, high tenacity, also if they are focused, can be quite accurate with their weapons not to mention they breed at a remarkable rate. The Covenant used the high-breeding rate of the Unggoy to their advantage in the Human-Covenant War, where squads of Unggoy very frequently overpowered UNSC personnel through force of numbers. The conflict on Harvest, and thus the Human-Covenant War, was in part started by an Unggoy named Yull tearing apart Private Osmo. Special Operations Grunts, which are known to wear black colored armor, are far more tenacious than the lower tiered ones, and have even been known to carry fuel rod guns and plasma launchers which makes them extremely dangerous foes. Even with weapons with high splash-damage, it is still extremely common for them to miss.

Unggoy are the only Covenant species to breathe methane rather than oxygen. Their combat armor/harness has an integrated methane re-breather system, as Unggoy are unable to survive for long periods of time without methane due to asphyxiation much like humans without oxygen. In games however, if the player manages to melee their methane tank off, they will not die. 

Psychology and behaviorEdit

While not overly intelligent or creative on the battlefield, Unggoy are one of the most gregarious and sociable of the Covenant races and possess a very strong pack mentality, often associating with each other in groups. Although they are quite capable of handling weaponry and operating vehicles and machinery such as Ghosts and Shades, Unggoy are generally rather simple-minded. There are exceptions to this rule, however: The Unggoy Deacon Dadab, for example, was noted as being quite intelligent for an Unggoy, as demonstrated by his ability to learn and communicate in Huragok sign language. Grunts can also be found working the land of Sanghelios. They sometimes use a recreational drug in the form of a gas they mix into their methane tanks called infusion, sometimes referred to as "the gas". It was found by ONI operative Evan Phillips.

The Unggoy seem to outnumber the other races to a large degree and might offer impressive resistance if properly organized. They have been called "cannon fodder" because their Sangheili or Jiralhanae leaders will often send them out to serve as a distraction, rather than actually having them effectively engage an enemy in combat. This numerical superiority and pack mentality allows for their sense of cultural identity to remain, despite a number of hardships, including their extreme subservience to the other races of the Covenant, as well as the dark time following reintroduction after the activation of the Halo Array.

An inherent psychological advantage possessed by the Unggoy are their unburdened neural pathways, which allow the Unggoy to absorb knowledge more freely compared to the other Covenant species. As such, they are often tasked with monitoring space for traces of human communication. In addition, many Unggoy have developed a clear understanding of two or even three human languages. This advantage serves as a river of confidence in times of great stress for them.

Unggoy generally follow a few short, simple guidelines given to them by the Sangheili; namely "When in doubt, shoot." or "Stay out of the way, live another day." Despite being held in low stature in the Covenant, many Unggoy appear to be strong followers of their religion. Their Deacons will often hold sermons onboard ships to boost the morale and teach the Unggoy onboard about the Covenant. For instance, a Deacon named Dadab gave sermons and taught the Unggoy on board a Jiralhanae cruiser about the Covenant and its religions. The Jiralhanae allowed Dadab these teachings because they believed that it would help the Unggoy become more competent and helpful.

They often gamble with each other and often play games; one in particular, hunting rock, involves two Unggoy competing to kill the most scrub grubs.

Anatomy and physiologyEdit

Unggoy share a number of features with different animal species on Earth. Like primates, they walk both bipedally and with the aid of their over sized forearms albeit in a manner similar to a chimpanzee. However, their bodies are armored with a hard exoskeleton as with crabs and insects. Their mouths have a set of small, pointed teeth, much like reptiles. However, the UNSC has classified them taxonomically as being most similar to Earth arthropods.

Unggoy are on average about three to four feet tall and are relatively weak compared to other Covenant species. Although they can easily walk upright on two legs, they may often use their arms to move in a quadrupedal fashion. While carrying armaments, they are forced to walk upright so that they may support their weapons with their hands, but while trying to flee, or while patrolling without a weapon drawn, they use their over sized arms as forelegs to add speed or stability to their gait. Their eyesight and hearing is average, and seem to have a very well developed sense of smell, sometimes sniffing the air to detect traces of foes or hidden enemies. This is facilitated through the olfactory membranes installed in their masks.

Unggoy also have thick, bio-luminescent, light-blue blood, possibly a result of methane-based proteins in the blood to facilitate methane-based respiration. Like Earth's Horseshoe Crabs, it is possible that their blood is blue due to high copper content.

Unggoy have over-sized forearms, while their upper arms and thighs are seemingly small. This has allowed them to be quite excellent climbers. Spiny protrusions on their elbows help them scale rocky surfaces and may also be used to add force to their melee attacks. They also have an amazingly fast finger reflex speed, as they can fire a plasma pistol of the same rate a Sangheili can with a plasma rifle.

The Unggoy have flat, three-toed feet, with another toe on the back of their feet. While they are small, stocky, and lacking in agility, they are quite sturdy; most may be weak, as they seem to be unable to carry a weapon heavier than a plasma pistol, although certain Unggoy of higher ranks appear to be surprisingly strong, able to carry an undeployed plasma cannon or fire a fuel rod gun with one hand without toppling from the recoil. However, physical strength may not actually go along with rank; the types of weapons available to them may be a part of a "trust" issue with the other Covenant. As rank-and-file Unggoy are clumsy and tactically inept, more powerful weapons are likely only issued to those who are more disciplined and experienced.

Although they require an atmosphere to breathe, Unggoy are capable of surviving in the vacuum of space without sealed, full-body gear. Unggoy carapaces apparently can withstand the chilling cold and airless environment of EVA conditions, but they must employ sealed face masks in order to breathe, as well as presumably to protect their facial tissues.


Unggoy breed prodigiously, with large egg clutches and short childhood periods. This combined with the large number of young per clutch and rapid sensory-motor integration development was one of the primary reasons why the Covenant cleverly used the breeding habits of the Unggoy to their advantage in battle, deploying the Unggoy as cannon fodder (this would be play a key-role in their war against humanity). Overpopulation is a serious problem and in non-war times, strict laws are placed on Unggoy breeding.

Unggoy do value their ties to their offspring, but are usually separated from their families at an early age by the requirements of military service to the Covenant. They resent this greatly, but because of their low social status in the Covenant, they are unable to muster any response.


The Unggoy's culture has been largely erased by their incorporation into the Covenant. They have been granted very few civil rights in comparison to other members of the Covenant and on a good day they are treated like second-class citizens. Despite the advances in civil rights granted after the Grunt Rebellion, including the right to carry weapons and hold places among infantry units, their representation on the High Council is mostly powerless. The negative aspects of their existence are offset by the irony of their continued survival due to the acceptance of the Covenant. The entire species in no longer at risk of being eradicated by two consecutive horrible winter seasons, as they had on their homeworld of Balaho, a swampy planet with a methane atmosphere. Infant mortality is now below 50 percent. Average life expectancy has more than doubled (not including combat personnel). Geronticide is no longer a necessity for the survival of the tribe. Producing enough food to last through the winter season and burning plague victims no longer rank as the top two priorities on their daily chores.


The Unggoy homeworld of Balaho is a temperate, swampy planet with a methane atmosphere and naturally occurring pillars of fire. The cold season of their planet makes them highly covet any source of warmth and light they can find, mainly due to the "Blue Death". The planet is still in process of recovery from a global ecological collapse before the activation of the Halo Array due to overindustrialization caused by the Unggoy at the time.

Since their natural environment has a methane atmosphere, they would need to carry methane tanks and breathing apparatus with them whenever they travel into areas without high levels of methane in the air. Since all the other races of the Covenant and their human enemies, breathe oxygen, the Unggoy find themselves wearing breathing masks more often than not. They have been revealed to be inhabiting large environment domes that have airlocks and methane filters for them to breathe, while not in armor or restocking their methane reserves at battlefield methane tanks. They seem to have high-pitched and squeaky voices, possibly due to the different resonating properties of methane gas. The high-pitched voices are commonly regarded as humorous by most other races, since they tend to sound like frightened children trying to sound intimidating.