Uyetsoub (pl. Uyetsoub, [ə-jet-sɵb] /uh-yet-sob/)

The uyetsoub were an invasive species most known for their use of advanced mimicry to ambush prey, and for being one of few predators to purposefully targets sapients. Like most lifeforms in the mersanida sphere, they were extremely difficult to root out once they had nestled into a region.  

Etymology and Definition

The species’ name is lusoyan in origin, and is contextually translates to ‘trench beast’. While [ø-jet-ɧʊub] /ö-jet-stjoub/ is considered closest to lusoyan pronunciation, a more simplified [ə-jet-sɵb] /uh-yet-sohb/ is widely accepted and used.  

Origin of 'Trench Beast'

Uyetsoub was a descriptive name first used on Hsaylo, and quickly became the most well-known. It originally stemmed from a belief that the uyetsoub would grab people by the ankles through city drain grates. This belief remained persistent despite the fact that the grates required hefty tools to unfasten, and were purposefully built to be too narrow for anyone to get through.  

Origin of 'Shirtless'

First known use was on Lantegos, and the name spread to the nearby worlds Weörth, Kastor, and Papacalla.   The name stemmed from a belief that you could identify uyetsoub, and other dangerous individuals, based on whether they wore a shirt or not. This in turn originated from a myth in the Mynnes archipelago. Over time it became considered inappropriate in Mynnes and nearby regions to not cover your torso outside of your own home, a public shower, a swimming locale, or the beach. In some areas it was strict enough you couldn't go bare-chested while on your yard, patio, or balcony either.   Today, the myth and most of the superstitions that gave rise to the laws and customs surrounding shirtlessness have faded into obscurity. Only a few states on Lantegos still enforce the related dress code, though nearly all public locales in Mynnes still forbid entry unless 'properly clad'.      

Origin of 'Mimic' & 'Skin Thief'

As uyetsoub spread and more became known about them, call names relating to their ability to copy their prey came into use in various places. Of all the variations, 'skin thief' became the longest lasting due to its popularity in different entertainment media.  

History

It's not exactly known when or where uyetsoub first came to Rosepetal. It's considered the most plausible that they slipped in through the Tasiv's Tear before it was contained. If they reached the nearby Agalon in the Öden System, they could have used the chaotic evacuation of the world to their advantage in order to spread to new systems.   How they spread so quickly between planets after that was never fully mapped either, but perhaps they somehow continued being able to hitchhike on riftcrafts. The first confirmed sighting of a hominin-form uyetsoub was on the world Hsaylo, but there's been dozens of unverified sightings on different worlds prior.  

The Mimics

When it became known that higher intelligence uyetsoub were capable of convincingly pose as their sapient prey and infiltrate society, many states tried to find means of rooting out any potential 'mimics' — without risking to cause widespread paranoia and panic among their citizens.   Individuals belonging to a pseudo-religious group, calling themselves the Shroud, began to approach state leadership and offer their assistance in exchange for funding to continue research what they called 'the mentites' — species today categorized in the dissimulex, plenumeiron, and mercurin order of mersanida.  

The Mentite Campaign

After the infiltration and corruption of the Indivisible Self and other organizations came to public knowledge, the effect it had on the general populace was just as bad as — if not worse than — had been anticipated. With public security being too busy staving off public riots and vigilante mimic lynches, a branch of the Shroud called the Soulfire Sentinels were given temporary law-enforcement rights in several galactic states to find and exterminate uyetsoub and other mersanida vermin.   Over the course of three decades uyetsoub, innuampa, sejotai, and ranomaru were systematically exterminated. In the beginning this was exclusively done by the agents of the Soulfire Sentinels, but once the initial panic had calmed, they issued a program where civilians would be rewarded if they reported suspected mimics to an agent or security official, with a bonus if it led to a successful capture. Proper bounty sums were offered to certified mercenaries for the live capture of specimens.   Any actions taken by non-sanctioned parties beyond the above remained illegal and punishable at the full extent of local law, for the sake of protecting innocents.  

Extinction

The last wild uyetsoub was killed on Myrefall over 200 years ago. Shortly after, the mentite campaign was considered concluded and the Soulfire Sentinel's rights of law and jurisdiction got recalled in all states except the Lukariat. Upon their disbandment 5 years later, the specimen they still kept in containment for study was euthanized, and the species was officially considered extinct.   There are those that still believe uyetsoub to exist and reports of suspected sightings come in every now and then. So far all have been judged false.  

Habitat & Population

The uyetsoub were found in all climates aside arid, almost exclusively inhabiting regions that were to some degree urbanized and inhabited by sapient civilizations. Cities and towns were the primary nesting and hunting grounds for uyetsoubs but smaller settlements could also get plagued by them.   Population density fluctuated and was dependent on what species individual specimens imprinted themselves on. It seemed they kept very large territories and wouldn't overlap with others imprinted on the same prey as them. This meant even large and densely populated cities fit about two to four uyetsoub per resident sapient species. Suburbs and smaller communities rarely hosted more than one specimen imprinted on a sapient at a time.   The Soulfire Sentinels reported that they alone had exterminated circa 22.000 uyetsoub across 40 worlds by the end of the mentite campaign.    

Biology & Genetics

Uyetsoub were plasmoform organisms that gradually adopted the morphology and anatomy of the species they imprinted themselves on. This made them increasingly difficult to identify with age as their level of mimicry improved across repeated life cycles — henceforth referred to as iterations.  

DNA Editing

The ability to alter their biology partially came from interactions with their symbionts, who would store isolated strings of DNA copied from their host and from consumed prey. These strings couldn't be modified, but they could be switched out with their host's own DNA like pieces of a puzzle to achieve different functions.   In pre-imprint uyetsoub this was limited to triggering the creation and reabsorption of keratin spicules. In post-imprint uyetsoub, its primary purpose was to build up a second set of DNA that'd allow them to switch fully or partially between their own form and that of their prey. It'd typically take four to five iterations before an uyetsoub had enough genetic material to pose as a near-indistinguishable member of their prey species.    

Life Cycle

Uyetsoub had an average life span of five years, but had the possibly unique feature of creating near-identical clones of themselves to perpetuate their ego.   Each of these cycles — ending in morphogenesic assimilation with a donor organism and restarting upon birth into a new near-clone — were termed an 'iteration'. They appeared to retain most, if not all, of their memories and knowledge from prior iterations, and there was no apparent limit to how many iterations they could go through.   More detailed information on uyetsoub replication can be found in the article on plenumeiosis.   A common sign of an uyetsoub nearing the end of its current iteration was increasing hunger. They'd go from feeding monthly or bi-monthly to eventually having to hunt several times a week. The feeding frenzy would culminate in live capturing one last prey, that they'd incapacitate and carry off to their nest.    

Growth & Dietary Habits

 

Pre-Imprint

Uyetsoub began as molluscan-morphs with elongated, bloated-looking bodies with no discernable head or tail. A wave-shaped 'skirt' circled the body laterally, where the tips acted as numerous prehensile limbs and made them surprisingly agile — they could effortlessly crawl and climb on most surfaces and swam in most non-acidic solutions. They ranged from wax white to pale beige in color, and were coated in a sticky bile. Nearly the entire ventral length was occupied by a maw.   Keratin spicules could be pushed out through the maw's outer lining to hold prey, or through the underside of the skirt to improve grip. Muscle relaxation usually triggered spicules to be withdrawn and broken down.  

Diet

Prior to imprinting on a species, uyetsoub were indiscriminate hunters. They tended to lack the intelligence and patience to create elaborate ambushes, but a common tactic was to fall down on prey from above. Due to being more impatient and reckless during hunts they were the sources of most sightings, witness accounts of attacks, and found remains.   Prey were typically killed, maimed, and devoured on the spot if possible, but specimens living in busier regions would develop the habit of moving prey to a secluded location early on. After dividing their prey into chunks, they'd devour and store them in a cavity behind the maw, where they'd be slowly digested with the help of a bile-like secretion infused with their symbionts. Most uyetsoub retreat to their nests after feeding, as they'd be bloated and sluggish while digesting food.   It was rarely difficult to recognize a site of feeding once found, as they in general were fast, violent, and messy feeders. Feeding sites, especially repeatedly used ones, could be nauseatingly gruesome.  

Post-Imprint

After completing their first replication and woke up into their new iteration, the uyetsoub would be imprinted on the species they chose as a donor organism. During the first iteration they could typically only mimic a vague body shape, skin/fur, and sounds. This would gradually improve each new iteration, until the fourth or fifth when they had collected enough genetic material to complete their secondary DNA set.  

Diet

Under natural circumstances, post-imprint uyetsoub exclusively fed on their imprinted species. Feeding on or replicating from a different species, even within the same genus, had possibly dire consequences.   As they accumulated experience across several iterations, their skills improved along with their intelligence. This led to increasingly devious hunting tactics, such as careful stalking and setting up ambushes to minimize noise and risk of being spotted.   They'd also in time learn to 'pre-digest' their prey by infusing them with their symbionts and leaving them in a secure location for a while. By the time they returned everything of their prey, save the epidermis, had liquified to an easily consumed protoplasmic slurry. It minimized waste, and left only the skin and any belongings behind once the uyetsoub was finished.  

Symbiotic Organisms

The uyetsoub were in co-dependent symbiosis with the microorganism mimicryne plenumeiron (M. Dilabuceres Fingadmeior), and it colonized their blood and other body fluids. When coming in contact with carbon, non-mersanida lifeforms they acted as an infective pathogen with viroid traits.   In exchange for a share of the absorbed nutrients, the mimicryne plenumeiron assisted its host's plenumeiosic processes. It also had the capacity of storing strings of DNA from both its host and infected victims.  

Medicine

As a consequence of their nature, a post-imprint uyetsoub would become susceptible to all of the conditions of their donor species were vulnerable to. They could accidentally contract a number of conditions either through direct contact transfer, infection, och from their symbiotes capturing damaged DNA.   They would also be at risk of drawing the attention of any parasites adapted to using their prey as a host, as well as get targeted by the same vermin and predators.