Headcrab Zombies

Headcrab Zombies, or simply Zombies, are former humans that have been attacked by Xenian alien parasites known as Headcrabs. These creatures attach themselves to their hosts' bodies, taking control of their nervous system and causing bizarre physical changes, such as an exposed chest cavity (known as the maw) and fingers that form into long, sharp claws. Zombies are a very common sight in Half-Life and even moreso in Half-Life 2.

Different Headcrabs form different types of Zombies when they attach to a host. As of the present, there are five known types of Zombies: Standard (or Classic) Zombies, Fast Zombies, Poison Zombies, Zombines and Gonomes. In all cases, the easiest way to defeat them is to aim for the Headcrab itself. Firing at the body does minimal amounts of damage and could possibly result in the Headcrab detaching from the host, ready to attack the player. The SPAS 12 is the preferred weapon to use against Zombies, as it can put a large number of projectiles into a compact area in an instant. Objects such as sawblades thrown by the Gravity Gun are also effective weapons to utilize against Zombies.

Although Zombies will not attack each other, they will engage any other entity, be it Citizens or Resistance Fighters, Combine forces, or Antlions.

Standard Zombie

Standard Zombie in Ravenholm. Note the gaping maw and long claws

The Standard (or Classic) Zombie is easily the most commonly seen of all the Zombies, frequenting the run-down and abandoned areas of City 17, Ravenholm, and Nova Prospekt. Once Citizens, they are distinguished by torn white shirts with a gaping maw with exposed and putrefying organs, long claws, and a Standard Headcrab attached to the head. At times, their muffled screams of "Oh God, help me!" can be heard, giving rise to the theory that they are actually semi-conscious despite the attached Headcrab. In-game dialogue made by Father Grigori seems to support this. Buzzing flies and statements about the awful smell made by Alyx Vance suggest that the body is rotting, leading to untold misery for the host to suffer from.

Although the Standard Zombies are very slow and easily avoided, they are dangerous in large numbers, and it is possible for the player to be swamped by hordes of them. If their body is cut in half by an explosion or an object, the upper torso may still be active, the Zombie crawling towards the player to swipe at him. Their attacks, while somewhat sluggish, deal ample amounts of damage. They are also able to hurl objects in their path at the player, often causing great harm.

Gonome

Gonomes are implied to be a further mutation from the Standard Zombie in Half-Life expansion Opposing Force. They are faster and stronger than Standard Zombies and generate a dangerous red saliva in their expansive maw that can be thrown as a projectile at the player.

Gonomes are not seen in any Half-Life installment except Opposing Force.

Fast Zombie

Fast Zombie, as seen at Ravenholm. Note the exposed muscle tissue and bone

First seen in Ravenholm, the shrieking, leaping, and terrifying Fast Zombies are some of the most challenging and dangerous foes in Half-Life 2. When a Fast Headcrab attaches to a host, the effects on the body are profound: almost all of the skin and internal organs disappear, leaving only exposed muscle tissue and bones. The noises made by Fast Zombies are some of the most easily recognized and unnerving in Half-Life 2, consisting of various gurgling, howling, shrieking, and moaning sounds as the host goes through intense pain and agony.

These Zombies are possessed of incredible speed and agility, able to jump impossible distances and move at a very quick pace, meaning that avoiding these creatures becomes very difficult. Just before reaching the player, the Fast Zombie will leap at high speed towards the him, and then attack with their claws, backing away from the player after each series of swipes (this is one of the best times to attack this Zombie). Although their attack seems to be somewhat weaker than that of the Standard Zombie, their blows come much more quickly, and in large numbers Fast Zombies are an extremely serious threat as the player is assaulted by a barrage of quick blows.

In Episode Two, the active torsos of Fast Zombies are first seen. Like the torsos of Standard Zombies, they quickly swipe at the player with one claw.

Poison Zombie

Poison Zombie with attached Poison Headcrabs

Another Zombie to make its first appearance in Ravenholm, the Poison Zombie is the result of a Poison Headcrab attaching to a host. This results in the host's body becoming extremely bloated and bruised, and is possibly the creation point for more venom for the Poison Headcrab. They emit various howling and growling sounds, and can often be heard by their restrictive and gasping breathing.

The Poison Zombie is unique in that the Zombie itself is not as dangerous as the passengers it carries on its back: more Poison Headcrabs. The Zombie itself can hurl these Headcrabs at a great distance and with surprising accuracy, and given the nature of the Poison Headcrabs and the number carried (anywhere from 3 to 5), the Poison Zombie demands respect, especially in the presence of other enemies. If it closes in with the player, it will attack with a very sluggish and moderately powerful swipe of its claws. It is also very tough compared to Standard and Fast Zombies. If killed, any Poison Headcrabs remaining on its back will jump off and attack the player.

Zombine

Zombine with a primed grenade near the City 17 train station

As a result of this, Zombines are incredibly tough, requiring at least two Shotgun blasts to the head to kill. Their attacks are also extremely powerful, and coupled with their quick galloping gait they are possibly the most dangerous Zombies of all. Only adding to this is the fact that Zombines will occasionally pull out a grenade and prime it, charging towards the player in an attempt to use it as a club. This results in the destruction of the Zombine and anything near it. However, the player can use the Gravity Gun to pull the grenade out of its hand, to use as he sees fit.

Trivia

• Zombies are referred to by the Combine as "Necrotics".