10 Grotesque Black Liquid Pathogen Mutations From Alien Universe- Explored – The Mysterious Goo

    The Black Liquid, also known as Chemical A0-3959X.91 – 15, was a living and malleable organic chemical developed by Engineers to turn organisms into vicious beasts. It is made up of millions of microscopic organisms that have the ability to both give and take life. The Black Liquid has the ability to fuse with the biochemical structures of other creatures, causing molecular and genetic changes.

    The Engineers are thought to have developed the Black Liquid as a bioweapon, with the Xenomorphs serving as an offshoot of that effort. The Engineers used to keep the liquid in various Steatite Ampules due to its exceedingly volatile and hostile nature. Naturally, many animals have arisen as a result of exposure to the black liquid; the majority of them have proven to be violent and hostile in nature, killing anything in their path.

    Although the exact date of the creation of the black liquid is unknown, it is safe to presume that Engineers have been using it for thousands of years. Engineers arrived at LV 223 millennia ago with the intent of unleashing the disease on Earth and wiping off the inhabitants. But, before that could happen, the Engineers were exposed to the black liquid, and the majority of the Engineers who intended to wipe out humanity were exterminated.

    Many years later, in 2093, the USCSS Prometheus landed on LV 223 in search of answers concerning humanity’s origins and the Engineers’ presence. Except for Elizabeth Shaw and the synthetic David, all of the Prometheus crew members died on LV 223. The single Engineer who had survived the black liquid also perished when he was impregnated by a Trilobite, which resulted in the birth of Deacon.

    Shaw and David boarded another ship for the Engineer homeworld, and when they arrived, he used ampules loaded with the black liquid to petrify and kill the hapless Engineers. Other species evolved into ferocious hybrid predators that attacked anything that moved at the same time.

    David invested several years into studying the black liquid and its effects on life forms. He concluded that the chemical A0-3959X.91 – 15 or the black goo or black liquid essentially served as a bioweapon that had the capability of exterminating any and all fauna. Once exposed, the black liquid would go on to change the genetic makeup and rewrite the DNA of the infected organism, making the organism extremely aggressive and nearly mindless.

    For instance, Fifield, a crew member of USCSS Prometheus, became violent and strong after exposure to the liquid and died only after taking heavy damage from gunshots, flamethrowers, and being run down by an RT Series Group Transport. Furthermore, the pathogen mutated several worm-like organisms in and around the Engineer temple, turning them into Hammerpedes.

    Like Xenomorphs, these creatures had acidic blood and, in addition, they could regenerate severed body parts. Charlie Holloway had sex with his partner Elizabeth Shaw after getting exposed to the black liquid. The exposure not only mutated Holloway but also altered the genes of Shaw, who got pregnant with a Trilobite despite the fact that she was barren. But since Shaw didn’t experience any more mutations, it can be safely said that the black liquid only changed her reproductive system.

    As we already know, the Engineers are a race of highly advanced and ancient humanoids. With a height of about three meters and extremely high intelligence, they are known to be the creators of many species, including Xenomorphs. It was the Engineers who led to the creation of Xenomorphs as well as humans. But when humans started to grow into a race that paved the way for their own doom, the Engineers wished to exterminate all humans. But that’s a topic for another day.

    If we believe that Engineers created the Xenomorphs as a bioweapon, a question that arises is against which organism did they design tjese weapons?  A frequently asked and debated question is whether Engineers created the Xenomorphs to fight Yautjas because apart from this, there’s hardly any sensible reason that would explain the creation of Xenomorphs.

    So, it is fairly possible that the Engineers created the Xenomorphs as a defensive weapon against the Yautjas, who hunted Engineers. But when even that didn’t help, the Engineers resorted to living a peaceful life as a last resort to shield themselves from the wrath of Yautjas, who didn’t attack unarmed prey because of their code of honor.

    This is why the Engineers were dressed in robes and wielded no arms in Alien Covenant. It’s quite a possibility that Yautjas started hunting humans in the first place because of their acute physical resemblance with the Engineers.

    Let us now take a look at a few species resulting from exposure to the Black Liquid.



    In the 2012 movie Prometheus, a synthetic named David tricks Holloway into consuming the black liquid. Later Holloway has sex with his partner Elizabeth Shaw. Although Holloway dies later, Shaw becomes pregnant with an alien creature despite the fact that she was sterile. Interestingly enough, the Trilobite that she gave birth to not only had an amniotic sac but also an umbilical cord. From the movements of the Trilobite before being extracted, we can assume that it would have worked as a belly burster if Shaw didn’t perform a cesarean using the Pauling MedPod 720i.

    Nevertheless, the Trilobite essentially worked as a face-hugger, but unlike a face-hugger that takes birth from an egg, the Trilobite came out from a womb. It is largely unknown how exactly a sterile woman could conceive it, but it is a widely accepted fact that Holloway’s sperm had its genetic structure altered, which in turn altered the reproductive system of Shaw.

    Initially, the Trilobite looked like a four-armed squid and was extremely aggressive for its size. Shaw tried to kill the creature by trying to decontaminate the MedPod, but it only fell unconscious. The creature soon developed into an enormous squid-like organism with several large and powerful tentacles, so much so that the tentacles could take down a fully grown Engineer.

    It had two holes at its back, presumably for breathing. Unlike face-huggers, the Trilobite didn’t leap onto its host but rather made them immobile by binding them within its tentacles. Once that was done, the Trilobite impregnated the Engineer with a Deacon with its feeding tube that was placed inside a largemouth.

    The Deacon was more humanoid than most Xenomorphs and also less mechanical. It had pale blue, insipid skin as if it were an organism that had been kept in formaldehyde solution for quite a long time. Once the impregnation was successful, the Trilobite died, just like a facehugger. In contrast, however, the Engineer also passed out, presumably from exhaustion, struggle, and lack of air to breathe. Although the Trilobite was named after the long-extinct arthropod, it doesn’t share many physical resemblances with its namesake.



    As we already discussed in our previous entry, the Deacon came into existence after a Trilobite impregnated the Last Engineer; we wouldn’t get into those details any further. However, it’s important to learn about the Deacon’s unique physiology. It had smooth, bluish skin tone and texture, with four fingers, a thumb, and plantigrade feet. That’s as humanoid as an alien can probably get.

    Furthermore, its upper jaw had teeth similar to those found in herbivores, whereas the inner jaw had smaller, sharper, and fewer teeth. Interestingly, the lower jaw extended outwards and appeared as an extra set of gums. Unlike typical Xenomorphs, the Deacon lacked a tail and possessed a pointy head. Initially, the Deacon seemed to be smaller than the Engineer, but that could be because of infancy.

    With time, it would have outgrown the Engineer himself. According to the comics, 126 years after the events of the film, i.e., in 2219, a vessel named Geryon reached LV 223 with its crew. The mission turned out to be catastrophic for most of the crew members, and only a few survived,  including a mutant construct named Elden and a Predator named Ahab.

    Elden, Ahab, and a few human survivors reach a mountain that they presumed was home to a human beacon. In an attempt to safely leave LV 223, they started to drill into the mountain, but to their shock and surprise, they realized that the mountain itself was alive. Furthermore, they discovered acidic veins inside the huge structure.

    It was now that Elden assumed that the Deacon had mutated heavily around the Weyland Ship Prometheus and turned into an organic mountain. So, you can see that the Deacon is very different from Xenomorphs, but the biggest difference lies in the hosts that they come from and the way in which the Deacon was born.

    While most Xenomorphs born out of humans lack limbs, the Deacon had its limbs intact at birth. We have known Xenomorph chest bursters to break the ribs of their hosts when they burst out of the chest cavity, but the Deacon used the pointy end of its head to come out of the Engineer. The creature looks nothing short of an elegant white shark in the dark waters of the Arctic.

    Mutated Human (Sean Fifield)

    Mutated Human (Sean Fifield)

    Fifield was a part of the crew of Prometheus. While exploring the Engineer temple, an impending storm forced the crew to return to Prometheus, but Millburn and Fifield, get lost inside the artificial structure and were forced to spend the night there until the time the crew didn’t rescue them.

    The both of them soon discover Hammerpedes, alien worms from LV 223. One of the Hammerpedes latched on to Millburn when he tried to touch it. Meanwhile, when Fifield attempted to remove the creature, it fastened its grip and broke Millburn’s arm. In a desperate attempt to save Millburn, Fifield severed the creature’s head, but the acidic blood melted the visor of Fifield’s helmet. The creature’s head regenerated, and it entered Millburn’s mouth via his suit. To make things worse, the room’s floor got filled with black liquid; it touched Fifield and mutated him into a grotesque creature as his face melded painfully. When the rest of the crew finally left to find Fifield and Millburn, many crew members were slaughtered by a mutated Fifield.

    Furthermore, his transformation made him fairly strong and resilient, he was able to withstand several shots in the head but succumbed when they incinerated him using a flamethrower, shot him with a shotgun, and ran him over by using an RT Series Group Transport.

    Before joining the crew of Prometheus, Fifield had served on several missions, and it clearly took a toll on him. He became pretty unstable and hostile as a person. Although he appeared to be a vibrant person, which can be judged by looking at his Hawaiian attire, the red mohawk, etc., he seemed to act like the tough guy of the crew. But at the same time, he displayed quite a few qualities that made him seem like a coward, for instance, his reaction upon seeing the Engineer’s corpse.

    Mutated Worms (Hammerpede)

    Mutated Worms (Hammerpede)

    The Hammerhead was a worm-like creature found on LV 223. It had pale, whitish-grey skin that appeared somewhat translucent, similar to a Neomorph and even the Deacon. They probably are mutated forms of indigenous worms found on the moon. They could grow up to four feet in length and had crests that resembled the hood of a cobra. These crests could be folded inward or outward around a Hammerpede’s mouth.

    As seen in the previous entry, they were incredibly strong for their size and girth; it could easily break Millburn’s arm. Furthermore, like Xenomorphs, the Hammerpede possessed acidic blood and could regenerate. Although regeneration is an ability that is found on several earthly worms, the process is not as hasty as was witnessed in the case of the Hammerpede.

    The exact reason behind Hammerpede’s aggressive nature is largely unknown, but it is believed that the Black Liquid generated the worms. As we already know, the black liquid generates and regenerates life, and these life forms grow from simple to more complex organisms through a series of stages.

    One of the deleted scenes from the Blu-Ray version of Prometheus shows that the crew of Prometheus discovers small worms that later go on to develop into Hammerpedes. But this doesn’t yet allay the doubts regarding their origin.

    It remains quite possible that the Engineers brought the Hammerpedes with them so that the organisms could serve as lab test animals. Interestingly enough, the hammerhead worms or Bipaliums found on Earth can also regenerate heads and bodies when cut in half. Each half develops into a new worm altogether, but the process takes quite a bit of time.



    As mentioned earlier, Elden belonged to the crew that was sent to LV 223, 126 years after the events of the film Prometheus. He was a constructor a synthetic that was more advanced than contemporary synthetics and also possessed a more organic body full of muscles and tissues. On LV 223, the astrobiologist Francis Lane injected Elden with the black liquid, after which he began to mutate violently.

    Francis was suffering from cancer, and he wished to use Elden as a test subject to see if the black liquid could cure his cancer. Although quite organic in nature, Elden was essentially a machine. After his exposure to the black liquid, it seemed that his body lost most of the cutaneous material. Reddish and white tones covered his body, and he developed two tubular tendrils that protruded from his back, and these tendrils would later mutate further to take the shape of an extra set of arms.

    The mutation made him powerful enough to take on several Predators and Xenomorphs simultaneously, and he could even withstand shots from Plasmacasters without an ounce of pain. The parts that got damaged during the attack would regenerate within seconds, revealing his enhanced regenerative capacities. Furthermore, his body could morph as per his will.

    For instance, while fighting a group of Predators, Elden transformed his stomach to develop into jaws with razor-sharp teeth. When he bit one of the Predators with this deadly maw, the Predator himself began to mutate. So, it seems that Elden was not just infected by the black liquid, but he became a carrier of the infection too. Furthermore, vegetation began to grow on whichever surface he touched.

    It seems that he also had some degree of control over Xenomorphs, and he somewhat reflected the skeletal visage of the Xenomorphs. As a synthetic construct, Elden was helpful and more trustful than necessary.

    It was his nature of trusting people that made Francis inject him with the black liquid, which in turn unfolded the disastrous turn of events. He became increasingly violent after the infection and went on a rampage. However, in the end, Elden merged with the organic mountain, which was believed to be a highly mutated Deacon.

    Mutated Yautja

    Mutated Yautja

    He was a typical Yautja who got bitten by a mutated Elden; the Yautja subsequently underwent several violent mutations that left him vaguely looking like his kind. The indirect exposure to the black liquid caused his height to increase to that of the Upgrade Predator, who was taller than most typical Yautjas.

    Furthermore, his eyes turned pitch black, which was similar to Engineers or the mutated form of Elden. Additionally, he grew an extra pair of arms that came out of his left shoulder. The mutation gave him increased strength, even by Predator standards.

    He could now punch his way into a bio-helmet and break it into halves; instead of the typical four mandibles, he possessed ten of them, and they could bite into the strong Yautja skull with relative ease. The only drawback of his mutations seemed to be his troubled breathing.

    Before his mutation, the Yautja used to be an accomplished hunter and belonged to the clan of a famous Predator named Ahab. These Predators were already on a hunting trip on a nearby planet, but when they learned of Elden and his massacre, they probably assumed that he would be a worthy prey, and naturally, they came to LV 223 to take down the mutated Elden.

    After encountering Elden, the Yautja, along with his clanmates, attacked Elden. However, when the Yautja charged on Elden from behind, Elden grew large jaws in his abdomen and bit the Yautja, who recoiled in excruciating pain while the others fought Elden.

    By the end, only one Yautja remained, and instead of continuing the fight, he offered Elden the title and mark of a warrior, but Elden was not interested. Meanwhile, the Yautja bitten by Elden began to mutate in a grotesque fashion. After the mutation was complete, the mutated Yautja attacked one of his own, so far as biting the other Predator’s face and killing him in the process.

    After this, the mutated Yautja even ate the corpse of his fallen brethren, revealing that he had developed cannibalistic tendencies. But he was soon surrounded by Xenomorphs, whom he dealt with relative ease. In the end, the mutated Yautja attacked Francis Lane, who himself had undergone several mutations by now. In the end, Elden came to Francis’s rescue, and together, they managed to end the mutated Yautja’s rampage.

    Mutated Engineer

    Mutated Engineer

    David had explained in Alien Covenant that the black liquid was designed to infect all fauna. It took several different forms and infected organisms in different ways. On a closer look, one may find at least four functions of the pathogen in the films Prometheus and Covenant. While some believe that these are four different effects of the black liquid, some are of the opinion that the Engineers created four different kinds of black liquid.

    These would be the creation form, the destructive form, the parasitic form, and the mutated form. In the prologue of Prometheus, an Engineer drank the black liquid and immediately started to disintegrate. Whatever remained of his disintegrated body began to cascade in the water. This hastened the evolutionary process on Earth as his DNA triggered a biogenetic reaction.

    The Engineer probably consumed the Creation Form of the liquid and seeded the world to produce new forms of fauna, almost as if the Engineers were the gardeners of entire worlds. The destructive form was also witnessed in Prometheus. It had the capacity of exploding the head of an Engineer. This form of black liquid was to be used to destroy humankind from the face of the Earth.

    And it was probably this very form that David had dropped on the Engineer homeworld in the film Covenant. It served as a bioweapon and seemed to break down and destroy tissue, killing the infected immediately. The tissues then erupt into tendrils and turn into yet another transmuted form of the black liquid.

    The Parasitic form of the black liquid causes others not only to mutate grotesquely but also leads to the development of other organisms like Trilobites and Deacons. Lastly, the Mutation form of the black liquid completely transforms an individual organism into an aggressive and violent creature that attacks anyone in sight. Two prominent examples of this kind of infection were Fifield and the Hammerpedes.

    Mutated Fish

    Mutated Fish

    The second issue of Prometheus Fire and Stone portrayed a bunch of mutated fish, possibly a result of exposure to the black liquid. The fishes had grown extremely large in size, some resembling that of a great white shark’s. But the most interesting feature about these creatures was the two sets of jaws with razor-sharp teeth. Just as one of the crew members tripped and fell into the water, they got attacked by these mutated fishes.

    Mutated Plant Life

    Mutated Plant Life

    When David released the black liquid over the Engineer’s homeworld in the film Covenant, he killed the entire Engineer populace. But the pathogen didn’t just infect the non-botanical lifeforms or fauna, it also mutated the flora of the planet. These mutated plants or fungi developed at various locations on the planet, and the first two victims of the film Covenant stepped on these egg sacks that burst to generate airborne motes that infected those who disturbed the egg sacks.

    These were almost the size of the eggs of a bird and were able to sense the proximity of nearby hosts. When someone was in close vicinity, they would spew clouds of microscopic motes into the air. Interestingly, these motes were the first stage in the gestation of a blood burster and the creation of Neomorphs.

    To sum it up, it can be said well beyond an ounce of doubt that all creatures found in the Alien films, games, and literature are fierce beasts. Although the franchise doesn’t necessarily fare well in terms of continuity, the beasts have become memorable and will continue to remain so for a few centuries from today.

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