Antlions are an alien race that have begun to spread rapidly over Earth. It is not defined whether they originate in Xen or are from somewhere else entirely, but they came to inhabit the planet somewhere between the events of Half-Life and Half-Life 2.

They, like most insects on Earth, construct a hive, despite being unrelated to Earth fauna. This hive is entirely underground. As seen in Episode 2, this hive is a combination of already existing caves and passages created by the Antlions themselves via caustic acid spit from Antlion Workers.

During Antlion spawning season, they repopulate by gathering in warm sandy areas, such as the coast. Since they are extremely sensitive to vibrations much like many comparable organisms native to Earth, stepping on the sand may cause them to become disturbed, rise, and attack the source of the disturbance. This is where their name is derived from, as this behavior is similar to the insect family Myrmeleontidae which has predatory larvae that usually digs a pit in the sand to lure and attack prey, this form of Larvae is also called an "Antlion".


Pictured above are the forms of Antlions you will encounter.

These include:

Antlion Soldier - The most common form of Antlion, will attack by getting close and striking their enemy with their front legs. They can jump great heights, so if you are constructing a fortress to combat them, a roof is necessary. They are a greenish yellow in colouration (Although a second darker version is sometimes seen).

Antlion Grub - The larvae form of Antlions, Antlion Grubs are quite disgusting, they glow a sickly yellow. They can be found in the thousands in and around the hive. They are cared for by Antlion Workers. They pose no direct threat to you and are best avoided in order not to agitate the Workers caring for them.

Antlion Worker - A white Antlion that resembles an egg-white colored ant in appearance. Their job is to care for the grubs, and they will almost never be seen outside of the hive. In addition to the attacks the Antlion Soldier posseses, the Antlion Worker can spit out acid at their foes, which is very deadly. This acid is highly corrosive and is also what is used to carve the passages in their nests. Like their brethren, they have a high capacity for jumping and can cross incredible gaps with the utmost ease.

Antlion Guardian - The most tough form of Antlion, the Antlion Guardian is a gigantic form of Antlion that is formidable on the battlefield. They will try to bludgeon their target with their over-sized head when close, and when they're far and angered, they will charge at their foe with a high speed with enough force to push cars or other heavy objects aside. They have been known to break through walls in this way, as well. Ancient Guardians are a variant of Guardian that have a glow similar to that of the grub, and serve as a form of protection for freshly spawned larvae, not seen leaving the hive (Unless in pursuit of one who has harmed their young.)
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Strategy Overview: When facing Antlions, a shotgun is effective, as at close range it is able to quickly dispatch workers and soldiers. When facing a guardian, side-stepping and using your highest-damage weapon is advised. You should also use sprint to put some distance between yourself and the Guardian. Additionally, unlike it's smaller counterparts, Antlion Guardians can't jump, so getting to higher ground is your best bet.

The Combine are a large empire of inter-dimensional origins. They have an imperial mindset and grow rapidly. Their method of expansion is to violently take over planets, enslaving the native species and stealing resources, incorporating any intelligent life as slaves or, in the case of less intelligent life, modified into Synths. This was the fate of Earth - the Combine had noticed the Resonance Cascade and quickly sent Synths to take over. It is a common misconception among players to believe that the Seven Hour war involved Overwatch Soldiers, however this is inaccurate. Overwatch Soldiers were only created AFTER the Seven Hour War was over. The Combine troops fighting during the Seven Hour War were all Synths, such as Striders, Gunships, and Hunters, and likely some varieties not seen in gameplay.

The Combine have no moral limit to warfare, and while their true motives are unknown, it has been shown they are willing to use any means necessary to obtain what they desire. They go as far as genocide and biological warfare.

The Combine Earth force's leaders are Advisors, pictured above, which are maggot-like creatures with robotic limbs and eyes, and levitating capabilities. They are the 'leaders' of the Combine forces on Earth in that they have no (visible) superior they report to and seem to have the authority to command any of the Combine's troops of any rank. In addition to this, they seem to act with relatively free will, as seen when Breen has an intelligent discussion with one late in Half-Life 2 (When he is begging for them to bring him through the portal so he can escape from death at the hands of Gordon). Advisors can directly eat the mind of any creature with their long prehensile tongue.

They do this by inserting their tongue directly into the back of the neck, instantly killing the creature (If they aren't already dead in the first place).

Advisors are quite physically frail and rely on a mix of their technology and levitation to survive. Most of the time they are in life-support pods located in the Citadel. They only leave the Citadel once it has begun to fall apart due to the singularity collapse in Episode 1, and are so secluded the rebellion was not aware of their existence until this point.

Besides destroying someone's brain or levitating them with a lot of force (Their levitation is strong enough to crush a metal oil-drum, as seen in Episode 2) they can also defend themselves by emitting waves that cause intense headaches, which can be seen when Alyx touches one of the life-support pods in Episode 1.

Pictured above are several members of Civil Protection, a Combine APC, a manhack, and a Scanner.

Becoming a member of Civil Protection, unlike becoming an Overwatch Soldier, does not require any brainwashing, and is completely voluntary. Citizens are tempted to join Civil Protection because members receive additional rations and better living-conditions. They are not well-regulated, and as long as they uphold the rules of the Combine are free to bully citizens and generally act maliciously towards the general populous. In fact, this behavior seems encouraged in order to keep the regular citizens downtrodden. Because of the lack of brain-washing, Metropolice are regular humans with no surgical modifications. This makes them weaker than their Overwatch counterparts.

Civil Protection members are constantly encouraged to join the Overwatch, hence losing their humanity in exchange for 'rank privileges'.

Civil Protection are found all over cities under Combine Rule, serving to enforce the rules the Combine have and to further control the remaining human population.

Their membership includes:

Metro-Cop: The base unit of Civil Protection, a metro cop has a uniform whose most prominent features are a bullet-proof vest and a gas mask (Similar to Soviet Gasmasks). They sometimes deploy Manhacks, and have been seen using stun sticks, USP-Match pistols, and MP7s (SMGs). They aren't very accurate using an SMG, and will attempt to fire from the hip as their training is poor quality. Because of this, if you are any distance from them, a metrocop using an SMG is generally low-threat. It's best not to underestimate them, though.

The main threat they pose is in their high numbers.

Their purpose in the Universal Union is mostly to protect Combine cities. They are used in such a way that they pit humans against each other, further oppressing them. When civilians are being slaughtered in the streets of the Dystopian Combine cities, metrocops are the ones doing it. This can be seen in City 17 on numerous occasions.

Strategy: The metrocops are some of the weakest foes you will encounter. Just grab some cover and shoot, they'll go down without too many problems


Manhack: The manhack is a formidable flying torture device, in essence. It will fly closely while emitting a loud humming sound and cut directly into flesh. Generally they are deployed in swarms. Manhacks are not actually very difficult to fight as they are quite fragile, the Universal Union mostly uses them to put an exaggerated sense of fear into citizens in order to keep them oppressed through a sense of dread.

Strategy: A pistol will do the trick. In addition, they won't take many hits from a crowbar before they meet their demise.

City Scanner: City Scanners are a piece of equipment used as a mobile camera. They will go around the city, taking pictures of anything suspicious. The only practical threat they pose is the temporary blindness they will cause upon taking a photo. If you're busy fighting other foes, this can be annoying or even deadly if they time the flash right. In a sense, they are almost like flashbang grenades in the disorientation they cause in combat.

Strategy: A crowbar or pistol can take them down with ease. Or, if you're not in combat with anything else, they can be entirely ignored.

Pictured above are the standard three units of the Overwatch. The Sub-human branch of the Combine Overwatch consists of brain-washed people who have their abilities to think for themselves removed. During the process of becoming a member of the Overwatch, their memories are erased and their brains are altered in ways that make them unable to challenge the Combine. They have superior training to Civil Protection and due to their brainwashing are more loyal than Metro-cops.

In addition, several of their body parts are surgically removed, including genitals. In addition, during the process they lose their hair. The purpose of this is to remove human urges and instinct and also to more uniformly make them identical to one-another.

Their skin is incredily pale, but this may be part of being stuck in a heavy suit without access to sunlight from long periods of time or part of the surgery itself, it is never specificied which is the case, although the first seems more likely.

They generally travel by foot, APC, or Dropships.

Combine Soldier: The basic unit of the Overwatch. Their mostly gray and blue uniform are instantly recognizable. They are used as a general purpose military unit, during peace times they mostly patrol the outer-rims of Combine territory and kill any Xen-Creatures/Refugees/Rebels they come across. They have the ability to use grenades. They use SMGs, and AR2s. They can only be seen inside of the city once the rebellion is in full swing.

Combine Shotgunner: A variant of the Combine Soldier. The main difference is their red uniform, skull insignia, and the fact that they use shotguns.

Combine Elite: A variant of the Overwatch who have a white uniform with red armbands and a red visor. They are usually found in the Citadel or serving as specialists in a squad of Combine Soldiers. They are much more likely to use an AR2 than a regular Combine Soldier. Through extensive surgery, they are even less human than their Combine Soldier counterparts, possessing even less capacity for independant thought. One of their notable roles is as Breen's personal guards.

Strategy: Almost any strategy will work for combating Overwatch units. Just grab some cover behind something sturdy, shoot at them with whatever is available, and think happy thoughts. Usually this will solve your problems.



Pictured above are Nova Prospekt Guards, which are variants of Overwatch Soldiers meant to defend the prison known as Nova Prospekt. Their uniforms bear a 'Nova Prospekt' label on the back. Unlike their soldier counterparts, it is not common to see one using an AR2, as they are mostly equipped with MP7s (SMGs) and Shotguns. They can only be found in Nova Prospekt, as well as guarding the beaches surrounding it.

Strategy: Same as regular Overwatch, with the added factor that they may also be using emplacement guns with spotlights, which will blow your cover if you're in the dark.



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Non-Standard Overwatch Units:



Combine Sniper: A Combine Sniper is an Overwatch member using a Pulse Sniper Rifle. Their location is generally given away by the blue laser-sights that their weapon emits. Their weapon has a semi-long reloading time which can be used to your advantage when moving from cover-to-cover.

Strategy: Unlike regular Overwatch soldiers, the fact they are found in cover (Such as hiding in windows above you) will necessitate explosives. Hand grenades or those launched from your MP7 will do the trick just fine.

Striders: Striders are massive tri-pedal synths, standing well above any Earth creature. They are used in liue of tanks and have both machine guns and massive cannons that can bring down entire buildings. They do not really see combat until the rebellion is in full swing, although they did serve during the Seven Hour War. During peace they mostly serve to intimidate citizens. This is why they are often seen patrolling the streets even during peace time.

Strategy: Striders' armor plating can deflect most bullets, so your main chance to kill them is with heavy weapons like the RPG or the MP7's mounted grenade launcher. Make sure you have some form of cover so you can avoid both their machinegun and their cannon (Which they only fire rarely, so you don't generally have to worry about it).



Pictured above is an Overwatch soldier with two Hunters.

Hunters are a type of Synth armed with a deadly flachette gun. In addition, their front legs are quite sharp and fatal up-close. Hunter Squads generally track-down high-value targets. They are almost always accompanied by a Overwatch escort, so beware if you see some headed your way. Hunters are also used as escorts for Striders, as seen during the assault on White-Forest.

They have some amount of strength, and can be seen bursting through doors and moving with high speed.

Hunters are often used in ambushes, as can be seen in the White Forest village during Episode 2.

Strategy: When fighting hunters, throw objects at them with the Gravity Gun, as this is their main weakness and is much more affective than simply shooting at them. Be careful of when they charge at you, and be even more careful that their Overwatch escort doesn't manage to sneak up on you if you're too distracted with the Hunter.


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Pictured above are the Combine's Air Units, which include:

Hunter Choppers: A helicopter variant that is piloted by several Overwatch Soldiers. It is capable of using a form of machine gun to pin down their targets, and it can also drop timed bombs. They are usually used to track down High-Value targets such as leaders of the resistance.

They are very versatile and can provide fire-support over a large area. When they have been damaged severely, the crew might begin to rapidly deploy bombs in an attempt to kill whatever is firing at them.

Strategy: The gun mounted on the Airboat is your quickest means of defense, and the only practical one you have. Ironically, the gun on the airboat was stolen from the crash of another Hunter Chopper, meaning that in laymen's terms, the Hunter Chopper's main weakness is itself.

Gunships: Gunships are Synths, which are organic creatures combined with technology. They, like humanity, were enslaved by the combine. They have been augmented with a propeller and machine gun. They are mostly used to pin-down enemies of the Combine and their main advantage over other forms of Air-support is their ability to shoot down rockets that are closing in on them.

Strategy: Launch RPG missiles at them. Be careful, as if you go for a head-on approach, the Gunship is likely to shoot down your rocket. Make sure you try to confuse it by swiveling around with the rocket's laser guidance system. Persistence is key.

Dropships: Dropships are Synths, they carry a semi-rectangular box mounted with a machinegun. From the box, they can deploy Overwatch or Civil Protection units. Dropships are useful for inserting units directly to the battlefield. Generally they are sent out in groups, as a single dropship can only carry about five personnel at a time. They are also seen at times carrying APCs, and striders.

Dropships' only means of defense is a machine gun mounted to the front of the box that carries their troops. If they are carrying an APC or Strider, they have no actual means of defense.

Strategy: Dropships generally aren't worth the ammo it takes to kill them, but if you must, your RPG is your best bet. Just remember that more often than not it will be much easier to kill whatever the dropship is carrying than the dropship itself.

The Universal Union also has several mechanical units at their disposal.

These include:

Rollermines: Rollermines are approximately basketball sized spheres with a blue glow. Their beeping sound is a clear indicator when they are nearby. They attack by getting close and then emitting a high-voltage electric shock. They are always found in groups, so caution is necessary. If they attach to a vehicle, it will become disabled, so they are a high-risk threat if you're driving to evade enemies.

Strategy: Punting them far away with the Zero-Point Energy Manipulator (Gravity Gun) is your main method of defense. In addition, they have a weakness to water, so if you punt them into it, they will explode.

Ground Turrets: Ground Turrets are Combine Turrets supported by three legs. When they see an enemy their indicator light will flash red and they will open fire. They are generally used to control an area through by creating defensive "Hard points". As such, they are often encountered in Combine facilites like Nova Prospekt.

They can sometimes be found arranged in groups of two or more if an area is particularly strategically important.

Strategy: Knocking a turret to the floor is your best bet to disable it. If a turret is your ally (If it is hacked, like the ones during the Antlion section of Episode 2), picking it back up and placing it the right way up will re-enable normal operations. Be wary that when knocked over it will fire erratically for a few seconds before being disabled, so make sure you aren't standing in front of it.

Ceiling Turret: Ceiling turrets are, as their name suggests, ceiling-mounted turrets. Unlike their floor-turret counter-parts, there really isn't a way to defeat these, and as such you must simply avoid them.
Another way to manuever past them is to have them be distracted by another enemy (Like a headcrab).

Ceiling Camera: A ceiling-mounted camera. These don't pose much threat other than giving away your location. They can be destroyed quite easily. If you wish to destroy them, use the crowbar to conserve ammo.

Thumpers: Thumpers are devices used to suppress Antlions. Antlions are sensitive to vibrations, so the pounding of the ground produced by a thumper is enough to keep them away. Generally, these are beneficial to you and should not be turned off. However, if a Combine squad is fending off near one, turning it off and letting them be swarmed by Antlions can save you some much needed ammunition or even help you avoid a firefight entirely.

Headcrab Cannisters: The Combine have weaponized headcrabs, as can be seen when they shell rebel fortifications/towns (Such as ravenholm) with them. This is a type of biological warfare, this is usually used so that the Combine can kill off any refugees/rebels without actually having to send in troops. The downside to this method is that sometimes the outbreak gets out of control (As seen in Ravenholm) and they have to position guards around the perimeter. This can be seen when you have just left the mine connected to Ravenholm and there is a Combine Sniper positioned nearby.

Headcrab cannisters are launched like mortars and usually contain 3-4 headcrabs that are released upon impact. It is presumed they are launched from the citadel and that they are also packaged there.

Headcrabs are aliens that come to Earth through the Xen portal during the Resonance Cascade. They take over their victim by hopping onto their head and latching on with a razor sharp beak that penetrates the skull of their victim. They then take over the body of the host and begin sucking nutrients from it, causing loss of muscle mass over time. Headcrabs come in several variants and are among the most common Xenian creatures found on Earth during Half-Life 2.



The basic zombies are created when a normal headcrab latches onto a host that is a regular human. When the hosts are taken over, they are still conscious, which is why they scream for help at anybody around them, as their vocal chords are among the only parts of their body they still control.

Headcrab Zombies are usually not that dangerous alone, but in groups they can be deadly.

They are fans of playing dead, so make sure all the corpses in a room you're walking into aren't just some headcrab zombies taking a convienent nap.

Strategy: The SPAS-12 (Shotgun) is the most effective tool for dispatching all-types of headcrab zombies, while simply using a crowbar will work for the headcrabs themselves.



Pictured above are Zombines. Zombines are created when a regular headcrab takes over an Overwatch Soldier. They are faster than regular headcrab zombies and can commit suicide by pulling out a grenade and running towards their targets. Take them out before they get too close. You can also steal their grenades with your gravity gun.


Pictured Above: Poison Zombies

Poison Zombies are abominations created when approximately four different Poison Headcrabs (Identified by their black color and hairs) jumps onto a single person. The host is ripped apart as the Headcrabs literally eat them alive. They are a form of bullet-sponge and are much harder to kill than other Headcrab Zombie variants. Be careful as they will attempt to throw Poison Headcrabs at anybody who gets too close.

Their cry is distinctive and some-what frightening. They have a high amount of strength as they can be seen doing things like breaking down doors.

Their body is bloated from being filled with toxins, this also erodes their flesh.

Upon death, they appear to moan in relief.



Pictured above are Fast Zombies. They are created when a normal human becomes host to a Fast Headcrab. A fast Zombie's nutrients are eaten away much more quickly than any other zombie variant, and it's muscle mass and skin are practically non-existant. Because of it's stream-lined design, they are agile, able to jump, run, and climb with great efficiency. Because of this, they are quite effective at ambushes.

Generally they use group tactics, they hunt in packs and are pretty much never found alone. For example, in Ravenholm they prowl the streets by the dozens, climbing up the gutters to reach you when you are on the roof.

They scream quite loudly and it is obvious when they are nearby. Their screams sound like a mix of agony and anger. When up-close their attacks are vicious.

Strategy: The SPAS-12's (Shotgun's) alternate fire is the quickest and easiest way to rid yourself of them. You may want to consider using grenades if they are swarming you. Your best bet is to pick them off from a distance before they can get in close enough to cause any serious damage.

I am a passionate fan of the Half-Life series and I simply love the lore. If enough people care about this, I may make several more parts, focusing on things like the lore of locations, weapons, and allies. They will go into far farther detail than this guide, and over time I'll likely improve this one as well.

Don't forget to rate and comment, as I'm always looking for ways to improve. Thanks for reading.

Edit: Wow, I didn't expect this to get so popular.


Thanks again for all the support!

Part 2 is out, it focuses on Half-Life 2's Main Characters! Read it here: http://steamproxy-script.pipiskins.com/sharedfiles/filedetails/?id=326293664

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Update: 6/15/2016 2:12 PM:

Fixed some general grammatical mistakes and added detail. Updated some screenshots.