The Xenomorph XX121, better known just as Xenomorph or the "Alien", is an extraterrestrial hive-based endoparasitoid with a multi-staged life cycle.

Known to be extremely deadly and hostile, these creatures require a host organism in order to reproduce. The appearance of the Xenomorph can vary depending on the host in which the embryo is implanted. The Human phenotype is generally around 7–9 feet (~ 2.13 - 2.74 meters) in height and roughly 181.43 to 272.15 kilograms (400-600 pounds) in weight, with a long, muscular tail and large, curved, oblong head. The Queen of this species is generally twice as large (although some Queens have been shown to grow even larger, some surpassing 30 meters in height if given time) and possesses superior speed, strength and intelligence compared to her common offspring.

Appearance: Xenomorphs, also known as Aliens, are extraterrestrial parasites with a biomechanical, skeletal appearance. They typically have elongated, cylindrical heads, often with a smooth or ridged carapace. Their skin color varies from black to gray, blue, or bronze. They are bipedal but can also move on all fours, and possess a long, flexible tail. Their inner jaw is a prominent weapon, capable of extending from their mouth to pierce skulls.

Here's a more detailed breakdown:

Body Structure: Xenomorphs have a tough exoskeletal structure, giving them a skeletal, biomechanical appearance.

Head: They have elongated, cylindrical heads, sometimes with a smooth or ridged carapace.

Skin Color: Muted shades of black, gray, blue, or bronze are common.

Limbs: They have two arms with long, sharp claws, and a long, flexible tail.

Movement: They are bipedal but can also move on all fours.

Inner Jaw: A distinctive feature, capable of extending from their mouth with significant force.

Acidic Blood: Their blood is highly acidic and can be used as a defense mechanism.

Size and Posture: The size and posture can vary depending on the host and maturity, with some being more hunched and others more upright.

Other features: Some have wire-like tubes around their bodies, and their appearance can differ slightly across various films.

Biology: A Xenomorph's physical appearance can vary widely depending on its life stage, hive, caste, age, and host. Its ability to incorporate genetic material from its host, coupled with the existence of numerous mutations and deviations which have originated naturally or artificially; makes the Xenomorph one of the most phenotypically diverse organisms in the galaxy.

A typical Xenomorph begins its life cycle as an egg-like creature (known as an ovomorph or simply egg) which, when detecting the presence of a potential host, opens up to release the second stage: a small arachnid-like life form (named the facehugger) which launches itself onto the host's face and impregnates it with an endoparasitoid larva. This parasite then consumes parts of the host from within and violently emerges from the host's chest cavity as a worm-like creature (grotesquely christened as the chestburster), which will quickly scurry away to find a safe place where it can molt and complete its metamorphosis into an adult Xenomorph, which happens, surprisingly enough, over the course of mere hours.

Adult Xenomorphs tend to share some common traits: a invertebrate-like body, including a protective dark exoskeleton, a long flexible tail, an elongated domed head and a toothed mouth hiding a secondary, extendable, proboscis-like inner maw. Little is known about their biology, but it is known that they eat with their inner or secondary mouths, not their outer mouths. This mouth is somewhat similar to the pharyngeal jaw of a moray eel. They also bleed an unknown and extremely corrosive fluid. This substance is dull yellow in color and often referred to as "blood", although whether it's used to transport nutrients through the body and/or serves principally as a defensive mechanism is not clear.

While the extremely corrosive fluids and tremendous resilience displayed by the creature might suggest an exotic kind of biochemistry, the fact that the Xenomorph not only feeds on Humans, but actually develops inside them, strongly suggests that its biology is carbon-based. The ability to inherit traits from its hosts also suggests that it incorporates genetic material from them, implying that the Xenomorph either has DNA, or is able to read and convert DNA into whatever means it uses to store genetic information. There is evidence that the genetic exchange is mutual (i.e. the parasite alters the host's DNA as well), given that Ellen Ripley's clones were created in an attempt to gain access to the Xenomorph Queen's genetic material, which wouldn't be possible otherwise.

Xenomorphs operate in hives made of a resin they produce, mixed up with their saliva fluids. The Queen can be generated in more than one way: from specialized royal facehuggers, or maturing from Praetorians, which in turn can mature from Drones or Warriors; by a process referred as 'molting'. Judging from the condition that any Xenomorphs can potentially 'molt' and grow into a Praetorian and then a Queen, the Xenomorph species is likely all unisexual and reproduces asexually by a process called parthenogenesis: a reproductive method practiced by many species on Earth and other planets. Alternatively, it's also possible that the aliens are either hermaphrodites or practice sequential hermaphroditism, i.e. being able to change sexes during life, as is the case with some species of fish and amphibians.-

Intelligence: Most Xenomorphs appear to possess an intelligence level equivalent to that of a typical primate. It's well within their capabilities to learn relatively quickly, gathering information and making advantageous use of their environment. Although they do not demonstrate Human and Yautja-level intelligence as a species (such as abstract reasoning, introspection and technological advancement), their Queen appears to possess considerable acumen in her social behavior and manipulation of Human technology, such as cutting the power of the LV-426 colony and operating an elevator. While it may take considerable time for them to learn how to operate machinery[4], other Xenomorphs have displayed fast reasoning and the capacity to find creative, counter-intuitive solutions to problems, as exemplified by a group which, after noticing that they were being contained, intentionally murdered the weakest so that the acid of the Xenomorph's blood would eat anything.

As the adult Xenomorphs are known to inherit physical characteristics from their hosts (for example, when a Yautja was infected, the parasite later developed into a "Predamorph" or "Predalien") it is possible that the intelligence level of the creature may be influenced by its host as well. Furthermore, being an eusocial species, it is possible that the intellectual capacity varies for each different caste.

Xenomorphs have demonstrated little emotion, though they are not completely devoid of fear, such as when they are in the presence of fire, which they are vulnerable to. They have also been shown to communicate pain through shrieks or screams when attacked.

It has been suggested that Xenomorph nests may operate under a hive mind, or a collective consciousness directed by the Queen, who can call back and give orders to her subjects, both telepathically and vocally with shrieks. In some cases, the Queen Mother Xenomorph communicates telepathically with potential hosts, inducing terrifying dreams and religious visions, which may even lead to the formation of cults with the Xenomorph as a god-like figure, not dissimilar to the cults of Cthulhu and other such entities. The most famous example of this phenomenon might have been Walter Golic, who received supposedly telepathic messages from a captured Xenomorph; which ultimately led him to release it and let it kill him. He called this Xenomorph "the Dragon", and viewed it as a god.

There is evidence that the Xenomorph hive mind also includes a collective memory that passes along even at a genetic level. Through the tests conducted on Ellen Ripley, it is revealed that the memory passed from Ripley onto the new generation of Xenomorphs allows them to read and understand different languages. Events on the LV-426 colony and the USM Auriga show that the species excels at observational learning. Another case of observational learning can be seen following a Xenomorph escaping its cell. It had learned that the consequences of attacking the observatory glass was a jet of extreme cold (possibly liquid nitrogen), triggered by a large red button on the console. When a crewman entered the now-empty cell to study the hole through which the Xenomorphs escaped, one of them entered the control room and activated the button using its inner jaw.

In the rare event that a Xenomorph finds itself under attack or otherwise vulnerable, it might display incredible creativity and cleverness. They are capable of moving quickly and silently in ventilation systems, despite their size, and will use such conduits for ambush, escape, or simply as an easy way to travel between areas.

Xenomorphs are conscious of the effects of their acidic blood, and will use it to their advantage - to break out of Human-constructed confinement, or as a weapon. They show some military tactics (such as retreating when overwhelmed), and can find ways to get around certain problems (such as pushing the red button to freeze a soldier in liquid nitrogen in the afore-mentioned incident). They know that the darkness is their ally, and break lights to create cover.-

Anatomy: A Xenomorph is equipped to be the perfect killing machine. They possess an exoskeleton much like that of a lobster, impenetrable to everything but the most powerful Human firearms (12-gauge shotguns, Pulse Rifles, and stanchion launchers are quite effective). Ash claims the creature's skin is made from "protein polysaccharides", so this would imply a substance similar to chitin. He also says the creature replaces its surface cells with polarized silicon, which is a very inert, heat resistant, and flexible polymer. This allows these creatures great environmental resistance. However, they are vulnerable to sudden, massive changes in temperature. It's been demonstrated that they can be destroyed by immersion in molten lead followed by sudden cooling with fire sprinklers, causing their silicon shells to shatter. They have a skeletal, biomechanical appearance and their skin color is usually black, gray, blue or bronze.

Attached at the ends of both of their arms are a set of long fingers and shiny, black, extremely sharp claws capable of slashing through almost anything within their grasp. Their tail is long and flexible. Some, though not all, individuals also have ridges on top, and a serrated toxic tip at the end of the tail to lacerate enemies.

They stand at around 7 feet tall (~ 2.13 m), averaging in anywhere between 140 and 180 kg; although size may vary wildly depending on the host chosen, as seen for instance with the "Jock-Xenomorph": a gigantic creature spawned from a Mala'kak host.

A Xenomorph's outer mouth is filled with sharp teeth, but their main killing device is the inner jaw that shoots out to penetrate directly into the victim's brain. The inner jaw (also known as an "attack tongue") is a muscular appendage on the inside of the Xenomorph's mouth. All Xenomorphs have this trait, excluding the genetically-engineered Newborn Xenomorph. It consists of a cord of muscle with a small but extremely deadly mouth-like appendage on the end. This attack tongue is able to punch through almost anything, from bone to Yautja armor.

The plasticity of the Xenomorph phenotype is one of the species' most notable features, and has resulted in physical traits that diverge from individual to individual and from hive to hive. As an example of how a host can influence the morphology and skills of the parasitoid, a Xenomorph spawned by a dog displays a distinctly canine body structure, digitigrade legs, quadrupedal movement, and greatly enhanced speed compared to those spawned by Human hosts, which are typically plantigrade and often bipedal.

Even among those spawned exclusively from Humans, different Xenomorph hives can produce highly divergent individuals. Some are taller and lankier, with an almost erect posture. Others are shorter and bulkier, and move more quadrupedally. While most have smooth craniums, others have ridges, which may be attributed to their age (i.e. those which have more time to develop may end up with ridges) and/or caste (ridges being associated with Warriors, and smooth features with Drones).

When it comes to their digits, there are at least three different patterns.

Some Xenomorphs have six fingers, with the index and middle fingers conjoined into one digit, ring and little fingers also conjoined, and thumbs on both sides.

Others are shown with five fingers, with the second thumb missing.

A third phenotype has only four fingers, though the middle two appear to be a fusion of two digits.

On at least one occasion, Human-spawned Xenomorphs were observed to have a digitigrade, as opposed to plantigrade posture. However, it should be noted that these were spawned by a Queen grown from cells derived from a clone of Ellen Ripley, making their genetic heritage muddled at best.

Some Xenomorphs have tails that are roughly the same length as the rest of their bodies, equipped with a small, almost surgical stinger-like barb on the end. This stinger can be, and has been, used to perforate victims, and may turn loose from the tail and remain lodged in the victim's body, not unlike a bee stinger. Conversely, other specimens have tails that are considerably longer, and armed with a large, knife-like blade at the tip and sometimes with ridges of spikes right before the blade, which may aid in swimming.

head: The most notable feature of the Xenomorph species is the elongated, banana-shaped head. A potential explanation for this curious shape may be that the head may store muscles required to power the Xenomorph's inner mouth.

In terms of eyesight, the Xenomorph appears to be entirely eyeless. However, there are features on its head which could represent eyes, which are usually hard-to-see due to the fact that they're small and the same black color as the skin.

Other proposed conjectures include that the eyes might be similar to a desert-burrowing lizard's eyes; meaning that they lay under a thin layer of skin, yet are deep enough that they are not visible from the outside. In that case, their eyes could be hidden behind their black carapace and they see through it, similar to a one-sided mirror (except in this case no one can see in, but the Xenomorph can see out). Some species of Earth fish, such as the Barreleyes, see through a transparent layer of skin; it is possible Xenomorph vision is similar. Another idea is that their whole head might represent one big insect-like eye.

Eyeless or not, it is widely assumed that a Xenomorph identifies enemies by sensing pheromones. This has never been explicitly confirmed nor denied, but a Drone will not kill a host that's already infected, so they must have some way of detecting the presence of the unborn parasite within.

Secondary jaws:

The secondary jaws (also known as the inner mouth, double jaw, or maw) are another disturbing feature of the species. It's assumed that they're powered by extremely strong muscles inside the creature's elongated head, that enable it to be quickly launched and retracted, similar to the tongue of a chameleon. The albino Xenomorph Drone has a very long inner mouth that can secrete resin that's used to build the walls of their hives.

The inner mouth is typically the Xenomorph's close-combat weapon, as opposed to its long-range tail. The Xenomorph lashes it out of its outer mouth, and it destroys anything it hits, being able to put a hole in a thickened Yautja skull and still have enough momentum to plunge another hole through the back as it escapes. Yautja take them as souvenirs of their kills.

The secondary jaw is powered by muscles, as seen when a Yautja rubs a part of the interior (resembling the gills of a crab), a feature that can be seen from the external midsection on each side of the head, ovular in shape. Muscles rub along here, letting the mouth be pushed out like a piston through the target the Xenomorph has acquired.

The Yautja-spawned Xenomorph (a.k.a. "Predalien") has the ability to use its inner mouth to implant chestburster embryos directly into a host's throat, like a facehugger. Since that particular Predalien was also on her way to developing into a Queen, it's possible that all future-Queens have this ability.

Dorsal spines:

Along the back of most Xenomorphs' bodies are a series of appendages that appear to have no clearly-defined function. It's still in debate what they are used for, with theories ranging from sensory organs to communication organs, to breathing apparatus, to defensive mechanisms, to structures that dissipate heat, to storing substances their bodies need, or to provide structures to carry around the young, underdeveloped chestbursters, the eggs or the facehuggers or as a counter weight to keep them from falling over when running. None of these ideas has been confirmed or denied so far.

One theory is that the four back appendages are used as a kind of radar that the alien utilizes to see through extreme environments or detect movements. It is also said that the dorsal spines are used to secrete and possibly store the resin used to build their hives.

It is interesting to note that Xenomorph Drones have been observed to bury themselves in the ground, yet their spines are still shown just breaking the surface[9], implying some use when connected to the environment. This may be either biological (breathing, heat exchange, etc.) or sensorial (detecting the vibrations of marines walking on the ground above).

Other hypotheses include:

Perhaps the spines separate the dominant Xenomorphs from the weaker ones, for example, the smaller the spines, the weaker the Xenomorph.

The creatures might come from a mainly amphibious planet, and perhaps the spines are a mechanism to swim underwater faster to catch prey. They do not seem all that hydrodynamic, but it's possible to suppose the spines might be used for stability, like the dorsal fins of a dolphin (not that their shape seems very much efficient at that either).

The spines might be spiracles that take in and filter the air around them, while waste is expelled through the mouth. It is widely accepted that they do not have lungs, so this is possible, and yet implausible because Runners (a.k.a. dog-spawned Xenomorphs), don't have them. But it may be that the Runners have lungs.

The spines might be used as a defense mechanism, to repel enemies that try to sneak up on them from behind or above.

They might also be traits that the alien acquires by chance when developing inside the facehugger, putting the legs of the facehugger on the back. The chestburster does not develop directly from the facehugger (instead, the facehugger plants the egg/larva that will become the chestburster inside a host), but it's not impossible that it acquires genetic traits from it.

They might be used to blend in with the hive web when under attack.

The spines may be for chestbursters to latch onto, allowing the adult to bring them to a safer location.

If the alien uses echolocation to see its prey, these may be what they feel the vibrations from.

They may be used to carry unhatched eggs to a new location when the Queen dies, allowing them to still climb walls while on the move.

The spines may be used to distribute pheromones - to distinguish one from another, and from other hives.

The spines may allow a facehugger to hook their spider-like legs until a victim is near. The facehugger will let go of its crude form of transportation, find the victim, and proceed with the process of laying eggs.

The spines may also act as a counter balance, much like a cat's tail, so that the Xenomorph does not fall forward when running. Though in truth, a cat does not require a tail to balance properly while running, it more so helps to balance upon thin surfaces like fences and the backs of chairs, and since the Xenomorph already has a long tail, this idea has little credence.

They may be used for breathing, as it's possible that the inner jaws serve only offensive purposes. This also makes sense if one considers that they may have come from a swamp-like planet, where they would lay in wait for prey to wander by. This would also explain the 'dome' over their eyes (assuming they have eyes), which may have functioned similarly to a camel's second eyelids: allowing the alien to see, while preventing stuff from getting in its eyes.

The "Runner", a Xenomorph born from a dog or other quadrupedal host, is notable in that it doesn't have dorsal spines. This could be an adaptation to make its body more aerodynamic and thus more efficient for running.

Tail:

It is accepted that the tail is an offensive weapon and little more. Though the creature can and will run on all four appendages, it often stands on its two hind legs so it can reach for its prey with its arms. While standing, it has also been seen to impale its victim with its tail, even to the point where it can raise a creature heavier than itself to eye level, possibly in preparation for a face-bite using the secondary jaws. This would clearly be impossible if the tail was needed for balance, as the already-shifting weight would be too awkward, causing the monster to fall.

As a weapon, the tail is extremely efficient, as it is long enough to attack from great distance and can be used in a variety of ways; for example, a Xenomorph has been observed to use its tail to knock the legs out from under a Yautja before trying to stab it.

The tail can be used in stealth attacks, since it is flexible enough to attack from a variety of positions, and is hard to notice if it is behind the enemy, or if the area is rather dark. Even when the sharp point is cut off, the tail is still deadly, as the Xenomorph can use the damaged tail to spray its acid blood from the severed tip over a wide area. Xenomorphs are also capable of using their tails as blunt-force weapons, clubbing their enemies with the vicious tail spikes.

The Yautja are often seen harvesting the tail bones of the Xenomorph to make acid-proof weapons.-

Purpose: The primary goal of a Xenomorph is the propagation of its species and the destruction of anything that threatens its existence. They are driven by basic survival instincts and biological imperatives, acting as a primal predator with a focus on reproduction and eliminating threats. This includes establishing hives and finding hosts for their young, the facehuggers.

Extras:

Survival and Reproduction: Xenomorphs are primarily driven by the need to survive and reproduce. They seek out hosts to ensure the continuation of their species.

Hive Establishment:

They create hives as a means of establishing a safe environment for their growth and development, and to protect their Queen.

Territorial Expansion:

Xenomorphs strive to expand their territory, seeking out new environments and resources.

Hostile Encounters:

They are inherently aggressive and will attack any life form that they encounter, especially those that could pose a threat to their hive or their survival.

Xenomorphs are not driven by complex strategic goals or technological pursuits. They are biological weapons, focused on survival and domination of their environment through any means necessary-

Physical abilities: The adult Xenomorph is a living weapon, noted for their ferocity and deadliness in any condition. Once fully matured, they have great physical strength and agility. They are masters of stealth; a favored method of acquiring prey is to wait in a dormant state until an appropriate victim strays near, and then drop down silently from behind or use their tail to impale whoever walks by. The prey is generally blind to the fact that a Xenomorph is present, due to its propensity to camouflage itself within its nest walls or the surrounding artificial environment, given their biomechanical-like appearance. The Xenomorphs will also use their pitch black carapace to their advantage, lurking in the shadows whilst waiting for prey to stray too close.

Xenomorphs are shown to be able to take extreme amounts of physical damage that would kill any earthly life form. An example of this is a Queen that survived a multi-ton exo-suit falling on her from over 30 feet. Xenomorphs are capable of surviving with limbs shot off, stabbings and even shots through the head (though total decapitation kills them).

Adult Xenomorphs are quick and agile, and can clamber along ceilings and walls: a skill they exhibit freely whether they are evading others, attacking, or hunting. They can survive in extreme temperatures, are well-adapted to swimming, can respire in harsh atmospheres, and can survive in vacuum for indeterminate lengths of time. Their movements tend to be silent, and they do not radiate heat as their exoskeletal temperature matches the ambient temperature. They also salivate profusely. This saliva is not acidic, though some Xenomorphs do have the ability to spit acid, which may come from their stomachs, a special gland somewhere in their throats, or acid pouches lining the head. This can be used to blind victims, much like a spitting cobra.

Due to the absence of clearly visible eyes, it is possible that the creature uses echolocation to see its environment, much like bats. It may be for this reason that Xenomorphs hiss almost constantly, though there is evidence that they can detect light and darkness as well. Xenomorphs may be able to find their prey through electro-reception. This is the method sharks use to detect even the most hidden prey. Creatures with the electro-reception sense can detect the electromagnetic field all animals produce, allowing them to locate their prey by its heart beats, even if the prey is immobile. This would explain how Xenomorphs always know where the Humans are. Furthermore, the Xenomorphs can also detect whether a potential host is already infected, likely by sensing pheromones.

Xenomorphs produce a thick, strong resin, which they use to build their hives and cocoon victims. Cocooning is a trait used by Xenomorphs to reproduce quickly. A Human, or any other creature, if dragged away, may have a cocoon of saliva and resin placed over them (their face left free), usually in an area where the Queen has produced a large quantity of eggs, so that the facehuggers are able to latch onto them easily and deposit a Xenomorph larva inside their chest. Much like termites, they mix their viscous saliva with solids. It shows amazing heat and moisture-retaining qualities. -

Vulnerabilities:

Xenomorphs, in all stages of their life cycles, have been said to have vulnerabilities to heat. The use of molotov cocktails and flamethrowers constitutes an effective technique to drive them off. The only Xenomorph not vulnerable to fire is the Predalien, which can secrete a layer over its body that cannot be ignited, although they are still visibly pained by temperature extremes, such as liquid nitrogen.

A rapid succession of extremes in both high and low temperatures apparently causes a thermal shock effect on a Xenomorph's exoskeleton. Xenomorphs are capable of adapting themselves to cold environments with little discomfort. However, the alien Queen is particularly vulnerable to fire, for unknown reasons.

Depending on the circumstances, Xenomorphs are shown to be both invulnerable and vulnerable to small firearms, ranging from 9mm to 5.56mm. This is seen when Vasquez and Lt. Gorman find themselves trapped in the ventilation between advancing aliens coming from both directions. Gorman fires with his pistol on one of them with no effect at all, instead it looks like the ammunition bounces off (presumably from the head carapace). In another occasion, however, Vasquez holds an alien at gun point and fires her pistol at the head, which apparently goes through and the alien rattles away, obviously damaged. High-caliber firearms, with the explosive rounds of a M41A Pulse Rifle may cause the creatures to detonate. High-energy beam weapons, such as the plasma weapons used by Yautja, appear to be the best way to kill the Xenomorphs since it can blow them off with a single shot and at the same time vaporize their acidic blood, though pulse rifles appear to be the best way to repel large hordes of them since they can fire non-stop and are not prone to being destroyed like the plasma weapons.

Xenomorphs are not invulnerable to melee weapons, although such equipment is likely to be destroyed upon contact with their acidic blood, unless the weapons are made from Xenomorph's bones. -

-**Genetic Adaption:**Due to horizontal gene transfer during the gestation period, the Xenomorph also takes on some of the basic physical attributes of the host from which it was born, allowing the individual alien to adapt to the host's environment more efficiently.

Through experiments, it was discovered that the embryo attaches itself to a major artery of its host, to get nutrients as it grows. It is presumed that the DNA from the blood it acquires infuses itself with the embryo's DNA to make up for its lack of genetic structure.

It may take on a thicker, bipedal form with a darker exoskeleton if it comes from something that stands on two legs, such as a Human. When the host is a four-legged animal, it may take on a more slender, sleeker appearance, where it too moves as a quadruped, and has a more reddish/orange-colored exoskeleton. It may also take on some facial features of its host (such as mandibles when implanted in a Yautja). Predaliens (Xenomorphs spawned from Yautja hosts) have a yellow-green partial skin covering their exoskeletons.

Furthermore, it is conceivable that it derives some level of intellect from its host. The quadrupedal Xenomorph seems easier to trick than bipedal ones, and the Predalien appears to have a better understanding of weapons being used against it. -

The xenomorph life cycle is a complex process involving several distinct stages that rely on a living host for development and reproduction. The cycle typically begins with a queen laying eggs, which contain facehuggers. These facehuggers latch onto a host's face, implanting an embryo, and then die. The embryo develops into a chestburster, which violently erupts from the host's chest, killing it. The chestburster then rapidly grows into an adult xenomorph, which can further differentiate into various forms like drones, warriors, or even a new queen.

Here's a more detailed breakdown:

1. Ovomorph (Egg):

The cycle begins with an egg, often laid by a queen xenomorph, containing a facehugger.

2. Facehugger:

When a potential host approaches, the facehugger emerges from the egg,attaches to the host's face, inserting an embryo into their chest.

3. Chestburster:

The embryo develops within the host, feeding off their life force, until it bursts out of the chest, killing the host.

4. Adult Xenomorph:

The chestburster rapidly grows into a fully formed xenomorph, which can be a drone, warrior, or even a queen.

5. Queen: (Optional):

A mature xenomorph can evolve into a queen, responsible for laying more eggs and perpetuating the cycle.

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