Antlion

"He won't last five minutes on foot. It's spawning season for the Antlions!"

- Leon

The Antlion is a voracious insect-like Xen creature that came to Earth after the Black Mesa Incident.

Overview
Antlions are social creatures which live in large underground colonies. The most common variety of the species is known simply as "Antlion", however their society is made up of a number of different strains which serve different roles.

Behavior and skills
Antlions are rapacious pack predators. Their favored method of accosting prey is to bury themselves in soft sand, sense for vibrations around them, then emerge and ambush the intruder. They usually form swarms so large that even a well-armed opponent will be quickly overwhelmed. Although they are blind they are extremely sensitive to vibration, which allows them to follow their enemies wherever they go once detected. This sensitivity can be turned against them; Thumpers, machines which pound the ground rhythmically, overload their senses causing them discomfort and preventing them from advancing on prey near them.

Antlions attack with their sharp claws and teeth. Those fleeing on foot or seeking higher ground will find no sanctuary from them; they will fly at opponents above or a distance away from them. They will fearlessly attack and pursue their target regardless of hazards they are faced with, and will continue charging even as fellow Antlions die in front of them. This includes charging into moving vehicles and into water, despite the fact they cannot swim. Antlions are both fiercely territorial and invasive. They will sweep into neighboring territory if it is not properly protected.

Pheromone Pods
Common Antlions seem to defer overall leadership to Antlion Guards, who direct them through the use of pheromones. Harvesting pheromone pods (through an unhygienic extraction method practiced by Vortigaunts) from the body of an Antlion Guard will allow a user to control the common Antlions. Users can command Antlions to follow by applying pressure to the pod. The user can also make Antlions move to a certain spot by throwing the pod to that spot. A note about these pods is that they do not provide protection against other Antlion Guards.

Antlions make excellent shock troops, once a pod is thrown, the antlions will charge at an incredible speed and take out whoever is in the immediate vicinity of where the pod landed. The Antlions can kill Combine Soldiers in one hit, and seem to be able to take more punishment than those not directed through the use of a pheromone pod. Any Antlion killed will quickly respawn, even when there are no burrows around (albeit it will take much longer than if there was a burrow) and will act on their own, attacking anyone who poses of a threat toward them. They are quite smart, for example, they will fly up to take on defended machine guns by utilizing flanking maneuvers.

Society
Common Antlions are the most visible element of a larger Antlion society, most of which is kept hidden in fiercely defended underground nests. It is not clear how Antlions breed. One resistance member is heard referring to a "spawning season" at the beginning of the Highway 17 chapter, but whether Antlions mate separately, have a queen/drone system or practice something completely alien to Earth sensibilities is not known. Their young begin life as larvae in blue honeycombs similar to those of bees. The extract of these larvae is highly prized by the Vortigaunts for its healing properties. The larvae grow into large grubs, which are attended to and protected by Antlion Workers and Antlion Guardians. Within this system common Antlions presumably serve as hunter gatherers. Inside their nests decomposed bodies of other creatures can often be discovered, trapped in the viscous silk the grubs produce as a food source, and some of their deepest chambers are pooled with blood.



History
Antlions were once farmed by Vortigaunts on their homeworld for their larval extract and a number of other purposes; Freeman's Vortigaunt companion in Episode 2 is heard commenting that the Antlion Grubs are "tasty". Since the Combine invasion of Earth and the beginning of the Portal Storms the Antlions have established themselves on Earth. They have obviously been very successful in doing so, possibly to the point of causing extinction to other kinds of Earth fauna. So widespread were the Antlions on Earth that the Combine had to install a large network of thumpers around Nova Prospekt, as well as a vast variation to the base of the Citadel. When these were shut down by Gordon Freeman's activities, both Nova Prospekt and City 17 were quickly overrun by Antlions, with chaotic results.

Tactics

 * Antlions are generally easy to kill, but are almost always encountered in numbers. Often once one has been killed, another will emerge from sand or a burrow. Antlion burrows can be blocked with large objects such as cars.


 * The best way to kill Antlions is from a distance, as their melee attacks are quite powerful, and will cause the player to flinch, making their weapon aim awry.


 * The player can knock Antlions over with the Gravity Gun, exposing their more vulnerable undersides, a fact they can take advantage of by switching to a secondary weapon to finish them off. It is possible to kill an Antlion by punting them repeatedly with the gravity gun, but it takes many hits and is not a practical form of attack. Although when, for example, moving a car to block a Antlion burrow, the Gravity Gun can be used to keep distance between the player and them.


 * If the player has pheropods, they can control Antlions. If trouble is met through an area guarded with Sentry Turrets or soldiers, Antlions can be used as a distraction. Antlions make very good area testers. Pheropods can be thrown ahead if an area is probably dangerous, and Antlions will often run straight through laser tripwires too.


 * Antlions in Episode Two are generally not infinite in number, as was the case in Half-Life 2 and Episode One. Stepping on their Grubs will not summon them, as was suggested in press releases - Valve removed the feature believing it would make the game (and the achievement for stepping on all 333 grubs) too hard.


 * Antlions will drown if lured into water by the player. This is useful when they are first encountered.

Behind the scenes

 * The original Antlion skin was orange and didn't have any green to it. However, it did have butterfly-like spots on its wings.
 * In the cut wasteland chapters of Half-Life 2, the player was to visit Antlion caves where they would meet the Antlion King and Antlion Grubs, among other enemies. The whole area and idea was brought back in Episode Two.

Trivia

 * The Antlion (scientific name Myrmeleontidae) is an actual insect; strictly speaking, the term Antlion applies to its larval form which does somewhat resemble Valve's creation.
 * The Antlion characteristic of sensing prey through feeling vibrations through the ground, then burrowing up and attacking said prey, may be a tribute to the Tremors film series, and is also similar to the Sandworms of the Dune series.
 * They are strongly similar to the Arachnid Warriors from the Starship Troopers films.
 * Antlions are coded to kill Combine Soldiers in one hit. This is not true of Civil Protection or Resistance Citizens, since Antlions were not intended to appear in the same locations as Civil Protection enemies.

List of appearances

 * Half-Life 2
 * Half-Life 2: Raising the Bar
 * Half-Life 2: Episode One
 * Half-Life 2: Episode Two