In appearance, a Vortigaunt is roughly humanoid with two legs and two arms, but has an additional arm protruding from its chest. This extra limb is a feature also found in other bipedal, sapient species from Xen, including the Alien Grunt and the Nihilanth. This similarity, along with other shared features such as red eyes and back-jointed legs, is strongly suggestive of a common ancestry with other intelligent Xen lifeforms. Apparently, this third arm is used for feeding, as both Vortigaunts and Alien Grunts are often seen bending over slain victims, feeding on it. Vortigaunts have mottled green-brown skin, sharp teeth, and clawed hands. Vortigaunts have a slightly hunched posture, and their faces are dominated by a large, single eye with a maroon scle and a red-yellow iris with a yellow pupil, surrounded by three smaller eyes. They also have a navel and four nipples, suggesting not only that Vortigaunts are placental (give live births), but also that they might be a species that is very similar to Earth mammals. Another interesting feature of the Vortigaunts is that they have no tongue or teeth on their lower jaw, yet they can speak English fluently, albeit with a strange accent and some sort of speech impediment when using S's
Intelligence and cultureEdit
Vortigaunts are very intelligent and social creatures. Throughout the Half-Life series, they can be seen in pairs or groups, and are capable of developing intelligent strategies. When faced with a superior enemy, Vortigaunts will often run away, and if possible, group together with other Vortigaunts to form a stronger force.
Brief glimpses into Vortigaunt culture can be gained by occasional speeches given by them in Half-Life 2, and in scenes during the original Half-Life. In the original game, Vortigaunts were enslaved by the Nihilanth and used as workers and drone soldiers. Based on comments by the All-Knowing Vortigaunt, it seems that the species has endured slavery for many generations ("We have endured these chafing bonds for eons, yet a single moment of further servitude seems intolerable!" as he says) and enforced servitude appears to have formed the bedrock of Vortigaunt history and culture up to the events of the first Half-Life. In Half-Life 2, Vortigaunts make occasional references to their species' culture. Vortigaunts have many traditions, including an apparent oral tradition of passing down poetry and songs from generation to generation.
Communication and the "Vortessence"Edit
Vortigaunts posses their own native form of vocal communication, which, in Half-Life 2, is referred to as "flux shifting", and can be heard in rare instances when two Vortigaunts are engaged in conversation. This method of communication likely involves frequencies which are not discernible to the human ear. According to the Vortigaunts, flux shifting cannot be understood by "those whose Vortal inputs are impaired", which may suggest that other inaudible components are involved, perhaps explaining why it is incomprehensible to humans. One of the most fantastic and enthralling examples of flux shifting is during the aftermath of the first Hunter attack in Half-Life 2: Episode Two, when the Victory MineVortigaunt that saves Alyx calls out over an immense distance to communicate with its kin, using two short but apparently highly descriptive calls.
By the beginning of Half-Life 2, Vortigaunts have learned to speak at least one human language, which, in the English language version of the game, is predictably English (in some international versions of Half-Life 2, Vortigaunts speak the appropriate language for the country of the game's release, i.e.: in the French language version of the game, the Vortigaunts speak French). However, the Vortigaunts' use of English is slightly strange, as they use archaic, even Shakespearean, words and grammatical structures which are largely obsolete amongst present-day English speakers. They also tend to refer to some characters by adding "the" before their name, such as "The Freeman" or "The Alyx Vance".
Vortigaunts believe in a binding life-force which they call the "Vortessence". Due to their use of this force, which remains untapped by humans ("We are a tapestry woven of Vortessence. It is the same for you if only you would see it.", as said by the All-Knowing Vortigaunt), the Vortigaunt species can communicate with one another telepathically. They believe Vortessence is the fabric of the universe, made of "vortal cords", of which everything is woven (and therefore everything is connected). The Vortigaunts are able to read and control this force for their electrical powers, nearly hive-mind telepathy and, likely, their ability to take power from objects. They can use their powers coupled with "the extract" of Antlion larvae to bring the nearly dead back to life (however, it is shown in Episode Two that they cannot do this alone).
It is also suggested that death is not permanent for a Vortigaunt, and that they might have the ability to "reincarnate" into a new body after death ("What seems to you a sacrifice is merely, to us, an oscillation. We do not fear the interval of darkness." as said by the All-Knowing Vortigaunt).
Behavior and skillsEdit
In Half-Life and its expansion packs, Vortigaunts are common enemies in both Black Mesa and Xen. While they usually attack aggressively, they often become timid when injured, preferring to run away rather than risk further combat and possible death. There is one area in Xen that houses a small number of peaceful Vortigaunts. However, if one is attacked they will become aggressive. Vortigaunts have two modes of attack: an energy attack in which they fire powerful green lightning-like energy beams that require a vulnerable period of "charging-up" before being unleashed, and when close to opponents, a claw attack. Significantly, in Half-Life all of the Vortigaunts wear green collars and wrist bands. Later events reveal these to be a means by which they are controlled by a remote master, the Nihilanth. Vortigaunts often act as support for Alien Grunts, making the Vortigaunts more likely to be able to use their attack, as the player is usually concentrating on killing the tougher Grunts. Throughout the game, the Vortigaunts can be heard taunting the player with what sounds like the word "die", and shouting a word that could be perceived as "Gordon" when the player approaches.
Half-Life 2 and its episodesEdit
In Half-Life 2, their electrical attack is far more devastating, as it tends to kill whatever it hits immediately and knocks the target back a considerable distance. Only objects with significant mass can resist being knocked back, such as the Strider (which appears to be fully immune to the beam) and Antlion Guards. These attacks occur twice during the single player game: when Gordon's view is restricted by rubble and when the Vortigaunt extracts Bugbait from the Antlion Guard. It is also suggested that Vortigaunts can siphon an opponent's life-force with their energy beam attack, as they are heard saying phrases like "Give over your essence!" or "Empower us!" during some of their attacks in Half-Life 2. In the Half-Life expansion Decay, the player plays as a Vortigaunt in a bonus mission, and the beam attack does indeed 'steal' life-force from enemies.
The beam attack is revealed fully in Episode Two, where a group of Vortigaunts use it to defend an underground outpost from a massive Antlion attack. It is shown to be powerful enough to kill Antlions and Zombies, and causes a shock wave strong enough to knock over other nearby foes. Freeman's Vortigaunt companion uses this ability to aid him in his attempt to raid an Antlion nest.