The Combine

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Combine
Political information
Type of faction / organization	Cross-universe/dimensional empire
Head of Government	Advisors (on Earth, true ruler(s) currently unknown) Wallace Breen (on Earth)
Subclasses	Overwatch (on Earth) Synths
Societal information
Capital / Headquarters	Combine Overworld City 17 (on Earth) Citadel (on Earth)
Armament	See Combine weapons
Technology	See Combine technology
Vehicles	See Combine Vehicles
Species	Various Humans (formerly; some remain) Vortigaunt (formerly) Shu'ulathoi The Nihilanth's species Countless others
Eras	Seven Hour War The Uprising
Game information
Designed by	Viktor Antonov (technology and architecture) Ted Backman (Synths and humanoid units) Dhabih Eng (early technology and architecture, Synths and humanoid units) Marc Laidlaw (story)
Entity name	npc_breen npc_advisor npc_combine_s npc_combinedropship npc_strider npc_metropolice npc_cscanner npc_sniper npc_clawscanner npc_stalker npc_combinegunship npc_hunter

 

"In order to be true to our nature, and our destiny, we must aspire to greater things. We have outgrown our cradle. It is futile to cry for mother's milk, when our true sustenance awaits us among the stars. And only the universal union that small minds call 'The Combine' can carry us there. "

― Wallace Breen

 

The Combine, referred to as "Our Benefactors" and CMB in propaganda, is the title of an immense and powerful inter-dimensional empire that conquered the Earth during the Seven Hour War, comprised of a variety of both allied and enslaved species.

Overview

The Combine Empire

A Combine Advisor.

The Combine is a vast and powerful multi-dimensional empire, spanning multiple parallel universes. Little is known about the Combine's origins and overall goals, but it can be assumed that their ultimate ambition is to conquer and assimilate the entire Multiverse.

Details of the Combine's leadership and administrative structure remain largely unknown. On Earth, alien beings called Advisors are responsible for liaising between the larger Combine and the occupying Earth-based detachment, acting through Dr. Wallace Breen, a human collaborator and puppet ruler who serves as the appointed 'Administrator' and humanity's ambassador to the Combine.

From what is currently known, the Combine assimilate intelligent species from the worlds they conquer and then manipulate these species through bioengineering and invasive surgery, twisting them to fit the Combine's pursuit of cruel perfection. The results of the Combine's re-engineering processes are "synths" — synthetic organisms augmented with Combine technology that serve a variety of functions within the empire, from weapons of war to mindless worker drones.

On Earth, the Combine notably uses their technology to create armies of cybernetically-enhanced transhuman soldiers forcibly conscripted from the enslaved human population, comprising the bulk of the Earth-based Combine Overwatch - a highly mobile and adaptive military force of co-opted humans turned against their own kind. Overwatch Soldiers have been surgically and psychologically altered to be obedient, deadly, and more resilient than normal human beings. They are also highly trained, and can adapt well beyond the confines of Earth, potentially in other universes if needed - in-game dialogue references the deployment of Overwatch units across the Combine Empire as "permanent off-world assignment."

Assignment on other worlds is often threatened as a punishment for soldiers who fail in their duties. Equally dire is the threat of "permanent off-world relocation" directed towards the normal Citizens for disobedience to the Combine regime. Dialogue from Wallace Breen suggests many of the extra-dimensional territories under the control of the Combine are uninhabitable for humans without life support systems.

Vocal stress is on the first syllable. The name is pronounced COM-bine, as in Combine harvester, opposed to the verb form com-BINE, as in "to join together or unite." Dr. Breen refers to the Combine Soldiers and Civil Protection as "The Transhuman Arm of the Combine Overwatch" in Nova Prospekt, implying that "The Combine" is an accepted name of the empire, at least among the Earth-based Overwatch.

It has since been revealed that the Combine originally invaded the homeworld of the Nihilanth's species and inflicted a campaign of genocide against them, with only the Nihilanth able to escape the slaughter by seeking refuge in Xen. It brought with it members of several species, both its allies and its slaves, including the Vortigaunts. Following the Black Mesa Incident and subsequent Seven Hour War, Earth then became the Combine's most recently known annexation. Earth's dominant species were modified to form a new arm of the Combine military, and the planet's resources were systematically stripped away.

Mighty as they are, the Combine are not without weaknesses, of course. Despite their enormous size, or perhaps because of it, they are "slow to wake" and mobilizing their vast power requires great effort and time. Their limited and slow teleportation technology, whilst still impressive in its own right, is a field in which even the Resistance is more advanced, as they are unable to translocate in local space the way that the Rebels can with their superior methodology. As such, they are vulnerable to clandestine guerrilla warfare tactics, and ultimately suffered a string of defeats resulting in a general collapse of their regime on Earth following The Uprising.

Combine Teleportation

The Combine is incredibly advanced technologically, being able to teleport to an entirely different plane of reality. Through this technology, the Combine can traverse entire universes and dimensions in their conquests. However, the Combine appears to have a limited grasp of localized teleportation. Dr. Mossman explains that while the Combine can teleport or 'tunnel' from one universe to another, they do not know how to teleport between different locations in the same universe, and are instead reliant on far less powerful means of local transportation.

The teleportation method developed by Black Mesa, on the other hand, enables intra-universal (local) translocation. As a result, the Combine has made it a strategic priority to obtain as much information on human teleportation technology as possible. Under the tutelage of Eli Vance and without his knowledge, Mossman aided the Combine to build a comparatively rudimentary teleporter with such capabilities in Nova Prospekt, but it was destroyed during Alyx Vance and Gordon Freeman's escape.

The Combine's teleportation is also far more resource-intensive than Black Mesa's teleportation. Since they possess only an extradimensional way of teleportation (in-between universes), an astronomical amount of power and gargantuan pieces of machinery are required to perform teleportation, as seen at the end of Half-Life 2, where Dr. Breen attempts to escape from the Citadel using a Combine teleporter. This teleporter requires a dark fusion reactor to power it.

Little is offered in the way of explanation for teleportation physics, but it's known that the Resistance's teleporters use Xen as a "dimensional slingshot" — whereby instead of entering and exiting Xen as Black Mesa originally did, teleports could instead "swing around" the borderworld and return to their own dimension without the need to use Xen as a layover. Combine teleporters cannot do this, instead apparently using "string-based" technology, similar to Black Mesa's "Calabi-Yau model." However, according to Mossman, the Combine fail at this method because they failed to "factor in the Dark Energy equations".

Combine on Earth

Combine Invasion

Newspaper clippings found in Eli Vance's lab in Black Mesa East depict scenes from the Portal Storm and the following Seven Hour War. Note the sections stressed by a yellow highlighter pen.

In the wake of the Black Mesa Incident, a catastrophic outbreak of violent meteorological events known as 'portal storms' began spreading across Earth and depositing alien creatures from Xen, wreaking havoc on a stunned population. The spacetime disruption caused by these storms then attracted the attention of The Combine, who subsequently exploited the rift created at Black Mesa to invade.

The resulting Seven Hour War, named so for it's infamously short duration, saw the technologically and numerically superior Combine quickly overwhelm the combined armies of Earth and unleash genocidal ruination on humanity, leading to an incalculable loss of life. When the fires died, it became clear that only the intervention of Wallace Breen, supposedly acting on humanity's behalf to negotiate a surrender, was able to halt the destruction.

Combine Occupation

Although the Earth is spared from annihilation by the surrender, the Combine promptly enslaved humanity, and rules over them with an iron fist. Combine-occupied Earth is a brutal and dystopian police state, characterized by widespread terror and mass oppression. The traumatised remnants of humanity were forcibly relocated to the surviving cities, which are now nameless and numbered, serving as walled-off prisons where the Combine keeps a watchful eye over a fearful populace.

Based on dialogue given by Isaac Kleiner during Episode One, it can be assumed that most Combine cities are dominated by a Citadel, an immense metallic megastructure resembling a large skyscraper, which serves as a local headquarters for the Combine in that sector - in the case of the City 17 Citadel, it serves as the main headquarters for the entire Earth-based Combine forces as well as the personal residence of the Administrator.

The Combine enforces order on Earth through the Combine Overwatch, the military arm of the Combine. In cities, an auxiliary detachment of the Overwatch called Civil Protection functions as a police force, comprised of unmodified human collaborators. Officers of Civil Protection are responsible for general law enforcement and engage in frequent brutality, including random beatings, summary executions, torture, impromptu raids, and other abuses of power in exchange for better food and living conditions.

This is a powerful incentive, as the oppressed Citizens of Combine cities are housed in squalid, dilapidated housing blocks often without basic amenities and are forced to rely on Combine ration terminals for nourishment, which is of poor quality and low nutritional value. The Combine can incentivise loyalty to the regime by offering extra rations as a reward for cooperation or withholding them as punishment. Movement is restricted between city districts, with reinforced checkpoints barricading roads as seen in the City 17 Trainstation Plaza.

Under the rule of the Combine, the downtrodden citizens of Earth are without basic human rights. No civic infrastructure or permanent bureaucracy is known to exist. There is no right of assembly, no freedom of the press, no representation within the government, and the regime frequently displays a callous disregard for human life. Any visible dissent is usually punished by death, forced conscription into the military machine, or worse. Mass surveillance through City Scanners allows the Combine to spot illegal activity, which is then relayed to Civil Protection's dispatcher, the Overwatch Voice. Undesirables and rule-breakers are deemed "anti-citizens" and forcibly re-educated, imprisoned, or killed outright.

More serious offenders are subjected to extreme and brutal surgical mutilation, and reduced to a pathetic existence as menial slave drones. Such procedures are carried out in Combine facilities such as the infamous Nova Prospekt, a former high-security prison turned Combine detention center where human prisoners are forcibly processed. Human processing is also believed to be carried out in the Citadel, alluded to by the large number of Combine holding pods and the sounds of distant screaming.

These crimes against humanity have been opposed only by the Resistance, a paramilitary force comprised of dissenters, scientists and refugees who use subterfuge and guerrilla warfare to undermine the Combine strategically, in the desperate hope of eventually freeing the Earth from their clutches.

Despite their obvious tyranny, the Combine has maintained extensive propaganda efforts to sway the population of Earth into willing loyalty. Promises of rewards for service and labour, as well as suggestions of immortality through their technology, were frequently made through Dr. Breen, Breen speaks of the Combine as Earth's saviours, bringing humanity to "the next step in (its) evolution." Hints of an underlying ideology are found in the Combine's propaganda. According to Breen, the Combine represent a form of technological, pan-universal transcendentalism, though of a decidedly sinister variety. It is unclear if this is Breen's own appraisal of the Combine or a view shared by the Combine itself.

Mind control

A Combine soldier connected to a memory replacement device.

The Combine are known to utilize a number of different methods of mind control in their rule over the remnants of humanity. A citizen at the City 17 Trainstation remarks: "Don't drink the water...they put something in it, t-to make you forget. I don't even remember how I got here", implying that the Combine drug the water supply with memory-altering psychoactive chemicals through Dr. Breen's Private Reserve, a brand of canned water widely available throughout City 17 and offered freely to citizens.

The mass broadcasting of propaganda through Breencasts, as observed in the City 17 Trainstation Plaza, frequently delivers hopeful promises of immortality and evolution through collaboration with the Combine. The Combine also have more direct means of controlling memory, as seen at Nova Prospekt and the Citadel, where humans are observed connected to Combine memory replacement devices, indicating that Overwatch Soldiers undergo forcible brainwashing during the surgical augmentation process. Similarly, officers of Civil Protection are encouraged to voluntarily accept memory replacement as a means to advance through the ranks.

Human genocide

Graffiti sprayed near Black Mesa East and other places (such as Matt's home), with a Combine (or possibly Resistance, or even a recycled Conscript) soldier holding a baby next to the word 'Caste'.

Killings

The exact death toll of the Seven Hour War is unknown; it is estimated to number in the millions, or perhaps even billions. Further massacres perpetrated by the Combine are also evident throughout Half-Life 2. In Route Kanal, a refugee base is raided and the refugees lined up and shot as soon as the player arrives, as part of a crackdown on the Underground Railroad. Such occurrences are believed to be commonplace.

The refugee town of Ravenholm is massacred after being discovered and shelled repeatedly by the Combine with headcrab canisters, wiping out the inhabitants by turning them into grotesque Zombies. In Highway 17, the player encounters a number of corpses, including some that have been burnt by the Combine in a bonfire. Within the final chapter of the game, Eli Vance explains to Breen that he has witnessed "genocide and indescribable evil."

Suppression field

Shortly after the Seven Hour War, the Combine established a suppression field that inhibited human reproduction, reducing the global human birth rate to zero. Isaac Kleiner explains this as "certain protein chains selectively prevented from forming". As a result, no children are seen throughout Half-Life 2 and its episodes, with the supposed last generation of humanity born nearly two decades before the game begins.

This deliberately engineered human extinction represents the culmination of the Combine's omnicide, effectively sounding the death knell for the human race. It is implied that the Suppression Field is emitted or maintained by the Citadel, as Episode One reveals that due to the damage sustained to the structure, the field is no longer active.

Depletion of Earth's resources

The draining of Earth's oceans is easily the most striking sign of the Combine's rule on the planet.

It is evident at several points in the game that the Combine is depleting Earth's natural resources. One of the most noticeable signs is that Earth's ocean levels have dropped dramatically, observed during the coastal chapters Highway 17 and Sandtraps, and the waterways of City 17 in Route Kanal and Water Hazard. The coastline is littered with boats and ships resting on what was once seabed, and various docks and piers are no longer standing in water, but are instead towering over the now traversable landscape.

At Highway 17's beginning, Gordon arrives at a harbor some considerable distance from the water's edge. Indications of the previous sea level judged by moss gathered on harbor structures (although the moss levels are somewhat inconsistent) places the former sea level several feet higher than what is now the ground. The book Half-Life 2: Raising the Bar mentioned that this massive, planet-wide water drainage is accomplished through the presence of a giant Combine "drain," actually a teleporter, which sends the water to other Combine-enslaved planets.

More generally, large parts of the game world are flooded with parasitic Headcrabs and toxic waste making them inhospitable to human life, showing the Earth as polluted and decaying under the rule of the Combine. Infrastructure is either breaking down (as with Highway 17, which is in a state of general disrepair and littered with old and rusted cars), or rendered useless (as with Nova Prospekt, where the traditional prison area is mostly flooded and run down).

Animals are rarely seen inside and outside of City 17, suggesting that most of Earth's natural fauna are critically endangered; although strangely, birds are seen regularly throughout Half-Life 2. The Fisherman in Lost Coast comments that there is no fish left to eat, only leeches that devour anyone who steps into the ocean, posing a further threat to humanity. Agricultural production seems to also have been greatly diminished, as Russell's comments during Half-Life: Alyx indicate that most species of livestock have been driven extinct. Additionally, City 17 itself is being devoured, as Combine Walls spread outward from the Citadel, consuming the city's buildings. It is unknown whether the Combine is purely using this method to destroy the city, or whether the Combine is gathering raw materials from the city's structures.

During the development of Half-Life 2, the Combine originally had an industrial facility called the Air Exchange, which gradually absorbed Earth's air and replaced it with chemicals and other murky gases. These gases were harmful to humans but most likely ideal for an environment that the Combine master race could inhabit. It was up to Gordon Freeman to travel to the Combine Air Exchange after the prison levels. Gordon's actions at the Air Exchange were to trigger the human insurrection against the Combine in City 17 but were dropped and made to happen due to Gordon's actions at Nova Prospekt.

Combine Propoganda

"Dove" poster commonly seen through City 17.

Imagery

The Combine heavily relies on propaganda to spread their influence on Earth and remind its residents of their presence. Combine units - humanoid and Synth - bear insignias, logos, and other Combine markings to denote their rank and status. Most of the time a propaganda poster includes two common Combine symbols, the most prominent being the 'claw' symbol, showing a sphere contained within a sharp claw-like structure, possibly visually alluding to how the Earth is now 'contained' by the Combine. Most Combine imagery is quite abstract, and the intended messages can be very subtle. Posters of this nature are frequently seen within cities, Combine facilities, and other areas under the influence of the Combine.

Breencast

Large video monitors are mounted on walls in public places such as town squares and railway stations around City 17. They are used by Wallace Breen to deliver propaganda announcements, known better as "Breencasts" and messages to the citizens, units of the Combine Overwatch and, later in the game, to address Gordon Freeman himself. The Breencasts are also broadcast in the homes of citizens via refurbished old televisions.

Combine technology

The Combine uses a combination of their own highly advanced technology and the technological resources of conquered civilizations, often blending the two together to create bizarre amalgamations of human and Combine tech. Most Combine technology is powered by dark energy, which is theoretically the most abundant source of energy in the universe. Combine reactors convert this dark energy into particles of exotic matter with observable physical properties, as seen in the Citadel's dark energy core and dark fusion reactor. It is apparent that the Combine's dark energy plasma is extremely powerful, as it allows them to power highly advanced machinery with anomalous properties that would otherwise be theoretically impossible to build.

Dark energy powers most of the Combine's teleportation devices, as well as weapons, vehicles, and other miscellaneous technology. During the occupation of Earth, human technology was also assimilated into the Combine's arsenal, with 'improvements' made to their design. The Pulse Rifle, for example, is essentially a Combine derivative of standard human assault rifles augmented with dark energy to form a highly potent directed energy weapon capable of disintegrating organic matter upon contact.

The Combine also use variants of human vehicle technology, such as armoured personnel carriers, trains, and helicopters, re-designing them for greater efficiency. Other vehicles and machines used by the Combine are clearly of non-human origin, with examples being the Strider and the Gunship, both derived from the living creatures of enslaved civilizations from Combine-conquered worlds.

Combine Soldier fighting Antlions along the Coast.

Combine Overwatch

The primary military force of the Combine on Earth is the Combine Overwatch (referred to by Dr. Breen as the "Transhuman arm of the Combine Overwatch.") comprised of human beings modified into "Transhumans" (or "post-human," as referred to by Dr. Kleiner). They are the most frequently encountered foes throughout Half-Life 2. Cybernetically enhanced, brainwashed and implanted with knowledge of tactics and military strategy, they are purged of most of their human emotions and obey the Combine with unquestioning loyalty.

Although seemingly used primarily on Earth for obvious reasons, several Overwatch messages indicate the Combine deploys its Transhuman soldiers to other Combine territories throughout its empire, sometimes as punishment. These modified humans have proven to be efficient killing machines against any foe that stands in their way.

It is important to note that Civil Protection units are not modified, and are fully human.

• Civil Protection: A quasi-"thought police" that patrol the cities, monitor the public airways, and conduct apartment raids. Considering Civil Protection evidently receive little to no biomechanical augmentation, some Resistance members, such as Barney Calhoun, join Civil Protection to work as undercover operatives to gain insight on the Combine's innerworkings and operations.

• Overwatch Soldier: The main military force of the Combine's occupation of Earth. Once free-thinking and emotional human beings, the Overwatch Soldier has been stripped of their humanity by Combine bioengineering. They typically patrol and enforce Combine law outside of city boundaries in more hazardous terrain, and garrison Combine military installations such as Nova Prospekt, the Overwatch Nexus, and the Citadel. Specialised units include the Shotgun Soldier and the Nova Prospekt Prison Guard.

• Overwatch Elite: The Elite soldiers of the Combine Overwatch. Deadly and powerful, they have undergone extensive augmentations and are seen guarding high-profile Combine military bases, or leading squads of regular soldiers.

• Stalker: Mutilated, drone-like slaves created from dissident Citizens and captured Rebels.

Overwatch Commando

Appearing only in Half-Life: Alyx, the Overwatch Commando is special forces group separated from the main military branch that is used to deal with particularly hazardous situations involving a dangerous environment and unconventional enemies. These soldiers have only been seen in the Quarantine Zone:

• Combine Grunt: The lowest rank in the Overwatch hierarchy, Grunts are the most commonly encountered Combine military unit in the game, apparently tasked with all matters not directly correlated with military confrontation. Grunts are often tasked with less-than-desirable, menial tasks above the paygrade of Civil Protection.

• Combine Ordinal: Ordinals act as commanders of Grunt squadrons and can be seen leading them throughout the Quarantine Zone. Though encountered together less often, other units appear to take orders from Ordinals as well, indicating they occupy a high station in the overall chain of command.

• Combine Charger: Well-armored units, Chargers specialize in direct confrontation of targets. Uniquely, they are equipped with a heavy shield to block oncoming attacks, and are capable of using this shield to temporarily blind their target.

• Combine Suppressor: Heavy units with equally heavy weaponry, Suppressors are incredibly formidable tank units who specialize in pinning its targets down with heavy fire, even from great distances, allowing lighter units to advance with little resistance.

Combine Synth

Synths are creatures that, through enforced evolution and alteration by the Combine, have been transformed into biomechanical weapons. Synths have come to fill particular niches in the Combine military, such as aerial assault craft and ground artillery. Once self-replicating organic creatures that originated from different worlds, they were enslaved and assimilated into the Combine, much like the humans of Earth.

Various types of Synth have been brought over to Earth by the Combine. Synths were likely the primary forces used by the Combine during the Seven Hour War. The human-derived Combine units and technology such as hunter-choppers and APCs would have only been developed after the Combine's rule on Earth had been established and human technology had a chance to be analysed.

• Advisor Pod: The escape pods used by the Combine Advisors.
• Crab Synth: Never actually fought, but seen in Half-Life 2 in the Citadel. Encountered in the Half-Life 2 Beta.
• Dropship: Primary aerial troop and supply transport of the Combine.
• Gunship: Assault aircraft that usually attack in groups of two for protection.
• Hunter: Medium ground assault units, similar to Striders only smaller in size.
• Mortar Synth: Never actually fought, but seen in Half-Life 2 in the Citadel. Also encountered the Half-Life 2 Beta.
• Shield Scanner: A biomechanical version of the City Scanner. Transports hopper mines into battlefields.
• Strider: Large ground assault units used by the Combine. Striders walk on three long legs, towering over the battlefield.

Non-Organic Technology

The Combine employs numerous devices and weapons used in the day-to-day policing and surveillance of the general populace. Some of these are merely human inventions that have been re-designed by the Combine, while others are either original or re-designed technology of other civilizations.

• Manhack: Essentially a flying, autonomous sawblade capable of tracking targets. Frequently used in clusters to flush enemies out of tightly cramped spaces, such as the sewer network under City 17.

• Rollermine: A ball-shaped 'mine' with a rudimentary targeting system that, once activated, follows anything it identifies as a threat and subjects it to electric shocks. They can also attach themselves to vehicles such as the Scout Car.

• Hopper Mine: A programmable explosive device that hops into the air and explodes when approached by an enemy.
• City Scanner: A flying security camera and mechanised scout that takes photographs of enemies and relays their location to its dispatcher. Also "dive-bombs" its target if subjected to enough incoming fire. Occasionally used as a spotter for Striders.
• Sentry Gun, Ceiling Turret, and Ground Turret: Programmable, autonomous sentry guns.
• APCs: The main transport vehicle for Civil Protection and a common sight within the cities. They are heavily armed and armored, complete with a guided missile launcher and mounted pulse cannon.
• Hunter-Chopper: Piloted by two members of the Overwatch, this aircraft is primarily used on long-range scouting operations or tracking mobile Resistance members. Its pulse cannon is highly effective, delivering a withering hail of gunfire. It can also deploy mines.
• Razor Trains: Combine trains made to transfer Combine Troops, supplies, and prisoners to locations.
• Headcrab Shell: A bioweapon consisting of a large metal canister fired as an artillery shell, releasing parasitic Headcrabs upon impact. Commonly used to destroy fortified targets, such as Resistance bases.

Combine Architecture

Most examples of Combine structures are large and imposing, with very blocky, monolithic shapes and sharp angles made of dull, blue-gray metal. Various tubes, wires, and pipes can be seen running throughout gaps in the walls and down along corridors and tunnels. Their buildings are purely functional, with no thought given for comfort, embellishments or decorations. Limited usage of aesthetics include infrequent usage of Combine imagery such as signs or logos, and artificial brightness creating harsh, dark shadows throughout the Combine's complexes.

Steep drops and lack of guardrails are common in Combine complexes as well. This lack of railing and deep falls are likely due to the Advisors' ability to fly and thus not needing bridges. Bridges are, however, in places where Combine soldiers move and operate; another example of the Combine's assimilation of human technologies. The material the Combine uses for their constructs remains unknown and is possibly extra-terrestrial in origin.

• The Citadel - A large, monolithic skyscraper looming over City 17, serving as the main headquarters of the Overwatch on Earth.
• The Depot - A building constructed for the intake of prisoners at Nova Prospekt.
• The Vault - A floating prison in City 17's Quarantine Zone used to store The G-Man.

Behind the scenes

• The Combine originally was to use Earth's building materials and twist them to construct their buildings. This mix of materials resulted in odd designs, such as the Citadel's interior made out of ceramic tiles. The material mix became the more familiar building material used by the Combine in the final version.
• Some Combine units were not from the final version of Half-Life 2 for various reasons, such as redundancy or unsatisfying gameplay. Some Combine subdivisions became others seen in the retail version. These cut enemies include the Combine Assassin, Beta Combine Elites, Combine Sniper Elites, the Alien Assassin, and the Conscripts (Which become allies with the Resistance after Gordon Freeman destroyed the Air Exchange). Other cut enemies include the Cremator, Combine Guard, Combine Synth Elite Soldier, Alien Combine Soldier, the Combine Super Soldier, Combine Mobile Mine, and the Sacktick.
• During the E3 demo, the Citadel is called "the Combine." This name implies the Citadel could originally have been the Combine.
• The Combine's name inspiration was likely by the 1962 Novel One Flew Over the Cuckoo's Nest by Ken Kesey. The novel's narrator mentions an oppressive, manipulative, and mechanistic authority that rules the masses, that he referred to as "The Combine."
• The Combine was originally going to use scrapped HECU voice lines and cut during the making of Half-Life 2.

Trivia

• It is unknown what happened to the Combine Commandos after the events of Half-Life: Alyx, given the fact that they're absent in Half Life 2 and it's episodes. A likely explanation is that they were upgraded into Overwatch Soldiers and Overwatch Elites due to advances in Combine technology.
• The Combine share some similarities to the Borg of Star-Trek, as both share a monolithic culture of bio-mechanical assimilation and seeming hive-mindedness.
• Though purged of their humanity and their free-will, Overwatch Soldiers will occasionally show emotion in their speech, particularly during combat. Snipers will panic and curse when grenades are lobbed into their nests, and Grunts will yell and scream when their flamethrower tanks are set alight.
• The dystopian society depicted in Half-Life 2 shows a variety of literary influences. The Breencasts are reminiscent of the 'telescreens' from George Orwell's 1984, which allowed Big Brother to address the citizens in public announcements. The Combine's method of forcibly brainwashing unwilling prisoners is reminiscent of the 'Ludovico Technique' from Anthony Burgess' A Clockwork Orange. The forced human sterility is a major plot element of P.D. James' The Children of Men.

List of appearances

• Half-Life (Nihilanth's appearance evidence only) (Retcon)
• Half-Life 2 (First appearance)
• Half-Life 2: Lost Coast (Non-canonical appearance)
• Half-Life 2: Episode One
• Portal (Indirect mention only)
• Half-Life 2: Episode Two
• Half-Life: Alyx