Yautja

   Yautja, sometimes called Predators, are physically distinguished from humans by their greater height, arthropod-like mandibles and long, hair-like appendages on their heads that are set into their skulls. Their bodies are resilient to damage, capable of recovering from multiple gunshot wounds and radiation doses which would be fatal to humans. They are much stronger than humans, having been portrayed as being easily capable of outmatching a conditioned adult human male and shattering solid concrete with their bare hands. They are also skilled climbers, and will readily move through trees or across rooftops in pursuit of prey. Though capable of surviving exposure in Antarctic temperatures for an extended period of time, it is implied that Predators have a preference for hot equatorial climates. Their blood is luminescent phosphor green in color. Their vision operates mainly in the infrared portion of the electromagnetic spectrum; they can easily detect heat differentials in their surroundings but are unable to easily distinguish among objects of the same relative temperature. A Predator's hunting helmet increases its ability to see in a variety of spectrums, ranging from the low infrared to the high ultraviolet, and also filters the ambient heat from the area, allowing them to see things with greater clarity and detail. While they are capable of breathing Earth's atmosphere,they sometimes use a breathing mask after losing their helmets. Their dietary habits are very intriguing since the creature regularly visits a slaughterhouse every two days to feed on the stored meat there.

Predator culture revolves around the hunting and stalking of dangerous lifeforms. After making a kill, Predators typically skin or decapitate the carcass, converting it into a trophy. Failure in a hunt results in the Predator involved committing an honorable suicide. It is often alluded to that the reason Predators hunt is not for sustenance or elimination of threats, but as entertainment or rite of passage, as they will only attack life forms that have the ability to provide them with a challenge. there are at least two different Predator tribes, which are engaged in a long lasting blood feud.

Predators made contact with early human civilizations such as the Ancient Egyptians, the Khmer Empire, and Aztecs, as well as a fictitious culture inhabiting what is now modern day Bouvetøya. Upon arriving on Earth, the Predators were worshipped as gods by humans, and they taught many of the civilizations how to build pyramids (an explanation as to why many of these different ancient societies had distinctly similar cultures and architecture), but in return expected sacrifices of humans for use as hosts for huntable Aliens. The Predators returned to Bouvetøya every century to consummate the bargain, until at one point in the ritual, the Aliens spread out of control, resulting in the Predators detonating a bomb that obliterated the entire civilization. Relations with humans and the Predators deteriorated from that time on; the Predators then viewed humans as little more than another quarry to hunt.

Predators feature prominently in the folklore of certain cultures; some Latin American people refer to the species as, "El Demonio que hace trofeos de los hombres" (Spanish for "The Demon who makes trophies of men"), while Jamaican superstition identifies Predators as demons from the spirit world. When hunting humans, Predators normally avoid certain individuals such as children and some adults if they are unarmed, though they will spare armed ones if they happen to be pregnant or sickly. A human who has managed to kill a Predator in single combat or has fought alongside oneundefinedis usually spared by the deceased hunter's comrades and given a gift (often a rare or exotic weapon) as a sign of respect.

A learner's first successful Alien hunt is completed with the marking of his helmet and forehead with the blood of his kill. Predators apparently keep Alien Queens in captivity in order to maintain a supply of eggs. The script of the Predators is expressed in the written patterns of dashes. These written symbols appear on the creatures' gauntlet displays, their helmets, architecture, and many other surfaces. The most common vocalizations of the Predators consists of a series of clicks, roars, snarls, and growls. Predators will mimic human language on occasion, and have been stated or shown to be able to understand and speak human languages.

Predator technology is distinctive in many respects, not the least of which is its ornate, tribal appearance masking deadly, sophisticated weaponry. at least one Predator weapon uses a metal that does not correspond to any element on the periodic table, and some weapons have been shown to be completely resistant to the effects of acidic blood belonging to Aliens. In addition, several of these tools make use of thermal imaging to track prey. The Predator's mask also houses a viewing system that fine tunes the creature's infrared vision by filtering out ambient heat, and also allows it to view in different spectra completely. The Predator's technology is advanced enough that the mask enables it to see in specific levels of X-ray and identify diseases and cancers, as well as picking up on pulse and heartbeat signals to track targets, The Predator also makes use of a light-bending cloaking device. Some aspects of their technology have been in use for millennia

