Headcrab

headcrab is a fictional alien species found in the Half-Life and Half-Life 2 computer game series created by Valve Software. Although small, slow-moving, and relatively weak on its own, the headcrab has the ability to quickly leap long distances. Its primary goal is to attach to the head of a suitable host, whereupon it takes control over its victim's body, rendering him a mindless zombie-like being.

A headcrab and host from the original Half-Life Additionally, the headcrab's alien physiology causes various mutations to rapidly manifest in its host, such as elongated claws, increased strength, and a sharp-toothed, sideways mouth that bisects the victim's chest cavity from neck to groin (this last feature has caused some fans to dub the headcrab zombies as "Mawmen"). The results of these mutations may depend on the type of host and/or the length of time the headcrab is attached. The gonome, is the next step of mutation. It is larger, stronger, more intelligent with a larger mouth in its chest cavity that produces some sort of volatile saliva the creature can throw. In most cases, a headcrab remains attached to its host until destroyed, although in Half-Life 2, they have the ability to detach from the host if it is damaged significantly. Removal of the headcrab reveals that the host's face has been largely eaten away by the creature, leaving behind merely a skull, eyes, and minor residual tissue.

A fast headcrab New to Half-Life 2 are two previously unseen variaties of headcrabs. The first variation is known as a fast headcrab, having longer, thinner, almost spider-like legs, which allows it move much faster. This type seems to produce leaner, skinless zombies that are astonishingly fast, agile, and have the ability to leap in long distances and climb pipes. The second variation, a poison headcrab, is identified by the white bands that encircle the area where the leg meets the body. To distinguish it further, its skin is a brown/black colour, with thick hairs on the joints of its long legs. It makes a very distinct and unpleasant sound similar to that of a rattlesnake's tail when it detects a viable host.

A poison headcrab A poison headcrab's bite injects an extremely powerful neurotoxin in its victim, producing a bloated, hunched-over "carrier" zombie that is usually encumbered with several other poison headcrabs hitching a ride on it. The zombie is able to hurl these headcrabs at enemies over a great distance. In addition, carrier zombies have extraordinary endurance, capable of surviving damage which even the best Combine transhuman soldiers cannot, such as a single .357 Magnum shot. Their claw attack is slower than normal, but quite fatal. All headcrabs have a green-yellow coloured blood although the poison headcrab has more of a vibrant lime green like its venom. Headcrabs appear to be quite low on the foodchain in their native Xen habitat, as both bullsquids and vortigaunts have been observed feeding on them.