Antlion (Half-Life 2)

The following is a list of creatures in the Half-Life series. Half-Life is a science fiction first-person shooter computer game series which consists of two full games, two episodic games, and three third-party made expansions, as well as a number of demos featuring exclusive content. The series has been ongoing since 1998. The game's setting and characters have been influential within the gaming industry, with The New York Times writing that with the innovative storyline "Half-Life became the Citizen Kane of the genre". In Maximum PC's review of the original game the monster design was given a rating of "excellent". The complexity of the creatures progresses as the gamer advances through the game.

Xen is a fictional world that houses numerous alien species in an alternate dimension set in Valve's Half-Life series. Note that these aliens are not originally from Xen, but use it as a border world to access other worlds in other dimensions, such as Earth.

Bullsquids are unintelligent, bipedal, highly aggressive creatures that appear throughout the Black Mesa Research Facility due to a dimensional rift. Bullsquids appear to be able to survive, if not thrive, in environments that are unfriendly or even toxic to humans, including sewers and pools of radioactive, chemical, or biological waste. In Xen, Bullsquids are sometimes found near pools of an unknown liquid that has healing properties to humans.

The body of a Bullsquid is vaguely similar in appearance to that of a small theropod, with two short, muscular legs and a thick tail that tapers to a point. The thorax abruptly joins the creature's head with no neck or other visible separation. A typical specimen stands roughly one metre tall and about two metres in length. Two slit-pupiled eyes are mounted on either side of its head.

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