Scorpius rex (S/F) / (CC-JW)

Scorpius rex (commonly misspelled as Scorpios or Scopius) is a medium-sized species of transgenic hybrid theropod dinosaur created by Dr. Henry Wu for the Jurassic World theme park operated by International Genetic Technologies, Inc. in 2009. While uncertain, the exact date of its creation has been suggested to be April 9 due to a deleted timeline note formerly found on the Masrani Global Corporation website’s backdoor terminal. Its scientific name means “scorpion king,” though the genus name is intended to reference not the scorpion itself but rather the scorpionfish (which was utilized as a gene donor). Scorpius rex was created out of Experiment E750, which yielded a specimen designated E750 after roughly a year of research. It is notable for being the first animal species known to have been created via artificial hybridogenesis.

Dr. Wu was authorized by the Masrani Global Corporation Board of Directors, CEO Simon Masrani, and Operations Manager Claire Dearing to bioengineer a species of artificial hybrid in order to attract investors and guests to Jurassic World on April 4, 2008. He began research and development almost immediately, having previously engineered a hybrid species of flowering plant (Karacosis wutansis) in May 1997 and having been eager to continue this line of study. In around a year, he succeeded in creating specimen E750, presenting it to Simon Masrani. The animal was considered too ugly to appeal to tourists and investors, but its unpredictable behavior and potentially fatal neurotoxin were ultimately the cause for which Masrani ordered it destroyed. Wu did not comply, keeping the specimen alive in cryonic stasis for research. The public, and many Masrani Global employees, were not made aware of its existence; there is currently no evidence that Dearing knew about the specimen. Wu and his immediate staff were the only ones to know that the specimen was not euthanized. It was used as a template to further the project, eventually yielding the larger and more complex Indominus rex. By that time, the project had evolved beyond simply making a park attraction, with Head of InGen Security Vic Hoskins persuading Wu to consider military applications.

According to the mobile game Jurassic World Evolution, this species and its descendants belong to the family Chimeridae. This family is fictional, and should not be confused with the recognized legitimate family Chimaeridae, which includes several cartilaginous fishes. Because of its hybrid origins, this animal cannot be reliably placed on the tree of life, but can most specifically be considered an averostran (including its tyrannoraptoran and abelisaurid genes), a saurian (including its snake genes), a tetrapod (including its frog genes), or most generally an osteichthyean (including its scorpionfish genes).

The genome of this creature was constructed by adding select genes from various other species into a template. While Wu’s process was largely kept a trade secret and details are mostly unknown, some of the donor species have been identified. Some remain undisclosed, but the known donors include:

  • Tyrannosaurus rex: Based on its use in the Indominus genome, it is most likely that this tyrannosaur’s genome was the template into which other genes could be spliced. Relatively few traits from this dinosaur show through, suggesting that not many of its genes are expressed in the final result.
  • Velociraptor antirrhopus: Genes from InGen’s Velociraptor were sourced to modify the anatomy of Scorpius rex, giving it enlarged and curved raptorial claws on its innermost toes and a set of powerful grasping hands. In Indominus, genes from Velociraptor were used to give the result heightened metacognitive abilities and allow it to interpret Velociraptor vocalizations as language, but these traits have not been observed in Scorpius; it has shown no ability to communicate with other species and does not appear more intelligent than an average theropod.
  • Carnotaurus sastrei: Structural genes from this abelisaur were inserted into the Scorpius genome in order to influence its anatomy, including the development of supraorbital horns and thick scales in the skin. Its skull shape is distinctively abelisaurid, unlike that of Indominus (which is heavily influenced by carcharodontosaurian, tyrannosaurian, and crocodilian genes) or Indoraptor (which is far more reminiscent of a eumaniraptoran, though still with crocodilian modifications). Unlike its descendant, it has not been known to produce or comprehend the vocalizations of this gene donor.
  • Scorpaenidae: An unidentified species of scorpionfish was sourced for genes facilitating the development of pterygiophores, informally called quills or barbs, as well as the venomous mucus glands characteristic of this family. The venom is one of the most powerful neurotoxins known, capable of causing respiratory arrest within a matter of minutes to hours depending on the dose and size of the victim.
  • Neobatrachia: An unidentified species of tree frog was sourced for genes which were most likely, as was the case with Indominus, intended to allow this hybrid to modulate its infrared output. This would help it adapt to tropical environments, but also appear to have made it capable of cryobiosis, the ability to survive being frozen. Many frogs use this ability to withstand northern winters. An unintended side effect of these genes was the ability to reproduce by parthenogenesis; the specific form used was most likely gynogenesis, as this is the method used by frogs. This is mostly seen in pond frogs rather than tree frogs, so it most likely resulted from latent genes that are not expressed in tree frogs but were reactivated in the Scorpius genome. The specific species of tree frog sourced is unknown; a chart for the Indominus rex implies that it was the red-eyed tree frog (Agalychnis callidryas).
  • Crotalinae: While currently unconfirmed, it is believed that genes from an unidentified species of pit viper were sourced to facilitate the development of heat-sensing pits in the skull of Scorpius rex. This is believed because it is capable of detecting thermal radiation, and in Indominus, the genes of a pit viper were utilized to give rise to the necessary physiological features for this trait. The exact species is not known; a “pit adder” has been referenced, but many snakes mostly in the family Viperidae are known as adders.
  • Tetrapoda: An unknown tetrapod species was sourced for structural genes to facilitate the development of opposable thumbs. These features are seen in some mammals, particularly primates, as well as some darwinopteran pterosaurs and frogs in the genus Phyllomedusa. Partially-opposable thumbs are observed in chameleons and certain theropods. The exact species sourced for Scorpius is undisclosed by its creators; this is also the case for Indominus.

The game Jurassic World Alive suggests that Monolophosaurus jiangi was sourced for this species, but this has not been confirmed in the film canon.


Scorpius rex is medium-sized for a theropod, considerably larger than Velociraptor but much smaller than Tyrannosaurus, placing it in between the size ranges of its main constituent genetic parent species. From snout to tail it grows up to 26.25 feet (8 meters), and it can stand between 11 and 12 feet (3.35 and 3.66 meters) tall; it usually stands on two legs, but is a facultative biped and is able to walk on all fours. It is more capable on four legs than Indominus, which can only crawl, but less capable than the galloping Indoraptor. Weight estimates for Scorpius rex are unavailable at this time, but as it is slightly larger and noticeably bulkier than its 1.1-ton (997.9-kilogram) relative Indoraptor, it is probably heavier.

Gallimimus bullatus as seen by the thermal-optical overlay of a Scorpius rex

The skull is significantly different than any of its relatives. While all members of its lineage incorporate abelisaurid DNA for anatomical traits, these show through in the skull structure of Scorpius: its snout is brachycephalic, meaning it is blunt and deep, and the small eyes are located high on its face. The jaws are powerful but short. All known specimens so far have shown an overbite, which is not characteristic of abelisaurids, but is probably a genetic engineering byproduct; it appears to be hereditary. Its brachycephaly and overbite give it apparent breathing problems. The teeth are conical and sharp; they are of mismatched size but those toward the back of the jaws tend to be smaller. Most likely, it loses and re-grows teeth regularly. The jaws cannot open as wide as those of Indominus, but still have a considerable gape. Its tongue is dark in color and somewhat mobile, but short.

Its nostrils are located on the upper side of the snout, facing forward like most theropods, and it has binocular vision as well. The eyes have red sclerae and vertical slit pupils, a trait it has in common with its descendants as well as some of its genetic parent species such as Velociraptor antirrhopus and Tyrannosaurus rex. Also like its descendants, the eyes are protected by thick nictitating membranes which originate from the medial canthus of each eye. These allow it to shield its eyes from damage and keep them clean while maintaining visibility. The skull of this animal is distinct among theropods in the extreme reduction of the fenestrae, smaller even than many fossil abelisaurids. It also lacks the heavy brow ridges of Indominus and Indoraptor, having only a small pair of supraorbital horns. There are quill-like spines on the head; these appear similar to the simple quills seen in some de-extinct theropods, but are actually derived from the pterygiophores of a fish’s dorsal fin. None of the spines on its body grow in distinct rows or patterns like those of fish fins, but instead are loosely organized into clusters. Those on its skull are very long and narrow, pointing backward. Overall its skull is quite durable.

Scorpius rex can contort its arms into positions which natural dinosaurs cannot.

This species has long and powerful arms, which end in dexterous hands. Like most genetically-engineered theropods, the hands can be pronated, a trait which does not occur in theropods naturally; this trait benefits the Scorpius as it allows for improved climbing and better grip on terrain. Each hand possesses four digits, the shortest of which is an opposable thumb. Each digit terminates in a sharp, curved claw. In general, the anatomy of its hands and arms is similar to other members of its lineage, though Indominus has the most advanced thumb and Indoraptor‘s arms are better suited to walking than those of the other two species. Scorpius has highly flexible shoulder joints, comparable to a primate; they are even more kinetic than those of Indoraptor, and vastly more so than any naturally-occurring dinosaur. The first phalanges of each finger are much thicker than the more distal ones, giving the hands a bulging appearance. In Scorpius, similarly to its relatives, there are spines on the undersides of the forearms; these are short and narrow, present near the elbow joint. While the spines of its relatives are quills related to dinosaurian feathers, those of Scorpius are not. Instead, they are bony spines more closely related to the fin rays of a fish’s pectoral fin. In terms of comparative anatomy, they are technically finger bones.

When it walks on all fours, its back slopes sharply upward with its hips about twice as high off the ground as its shoulders. This is because its humerus is about half the length of its femur, and likewise its forearms are much shorter than its lower legs. The metacarpals of the feet are around the same length as its fibula and tibia, giving it very long legs compared to its arms. On the hind end of its calcaenus bone, the largest bone of its heel, it has a hatchet-shaped backward-projecting bony process which breaks through the skin; the purpose of this feature is unknown and it may simply be a genetic engineering defect. Near each heel structure are a few very small outward-pointing spines, derived from the pelvic fin rays of a fish. This makes them homologous to toe bones. Its feet have three large clawed toes as well as a vestigial dewclaw; the innermost toe possesses a greatly enlarged claw which is curved and retractable. The curvature of this raptorial claw is much more dramatic than any other example, forming a tall arch rather than the simple crescent or sickle shape of a normal maniraptoran. The size of the claws is often asymmetrical between the feet. Like with the fingers, the first phalange of each toe is much thicker, giving the feet a bulging look. Its leg joints are very kinetic, though not to the same degree as the arms. Along with its climbing abilities, it is able to run at high speeds, though it is likely a little slower than the more lightweight Indoraptor.

Right footprint of a mature Scorpius rex (young human footprints to scale)

The body is similar to that of Indominus, being generic for a theropod without too many unusual modifications. Its most notable feature is the set of large, thick scales down its dorsal side, which are arranged in a single row spanning the body from the shoulders to the tail. They are slightly raised, giving its body a stepped profile when viewed from the side. Along with these, it has smaller, less raised, rounded scales on the sides of its body; these are derived from the round scales of Carnotaurus. Whether it is resistant to conventional projectile weapons like its descendants is unknown. Its tail is rather long, and unlike any of its relatives it is slightly prehensile. While the tail of Indoraptor is similarly strong and flexible, that of Scorpius is the only one in its lineage to be weaponized. It has spines on its tail, resembling quills like the others but again being derived from the pterygiophores of a scorpionfish’s dorsal fin. Each spine consists of a basal and a radial: the mucus glands are located near the basal, and the radial forms a detachable barb. Each spine is coated in mucus, which is extremely toxic. The spines of its tail seem to detach the most readily. These are the largest and thickest, so therefore they are coated with the most venom. It appears that they grow back fairly quickly after detaching; bone regrowth is not a common trait in advanced tetrapods, but is known in some reptiles and amphibians.

Little is known about its reproductive anatomy, though theropod dinosaurs typically have cloacae. In order to reproduce by gynogenesis like its tree frog genetic parents, it would need to mate with a related species, though owing to its wide range of sourced genes virtually any theropod would suffice. Therefore, its reproductive organs need to be compatible with those of the males of other species. Since it produces only female offspring, all Scorpius are female.

Its skin is scaly, consisting mainly of round or polygonal non-overlapping scales similar to those in many natural theropods (and unlike those of scorpionfish). Coloration is slightly variable but always dark: the entire dorsal body is a very dark gray or dirt brown, sometimes with lighter patches on the sides of the snout. The underbelly exhibits countershading, usually being off-white or very light yellow. This color extends to the insides of the legs all the way down to the heel. Underneath, its skin is more leathery than scaly; this is not dissimilar to the scorpionfish, which has scales on its dorsal side but lacks them on its ventral side. The spines are whitish, since they are made of bone, but tend to have blackened tips.

Scorpius rex produces a potent neurotoxin which is delivered via the spines. Being made of bone makes them rigid and sharp, capable of puncturing skin easily. The radials detach easily from the basals, which is most likely where the mucus glands are located. The mucus is the source of the venom, entering the victim when the sting occurs. So far, envenomation has been observed only from barbs on the tail, though the spines of its head, arms, and legs may also be venomous; these appear better suited to defense during combat than those of the tail which are used for offense. The venom helps it to down prey; Scorpius does not seem to be vulnerable to the venom of its own species. In addition to venom, it uses thermal sensing to track prey items. This is probably accomplished using heat pit organs similar to those found in crotaline snakes, which is the method used by Indominus; in this later hybrid the heat pits are located in the cranium. While pit organs do not provide a high-resolution image of their surroundings, the optic tectum of the brain (which receives information from the pit organs via the trigerminal nerve) overlays both the thermal and visual stimuli to create a combined image. In snakes, infrared sensing can detect radiant heat with a wavelength of between five and thirty micrometers, including the body heat of warm-blooded animals. Scorpius can detect within a similar spectrum.

A unique aspect of Scorpius biology, not observed in any other dinosaur (hybrid or otherwise), is cryobiosis. It is able to survive extended periods of time below the freezing point of water. This may be due to its tree frog genes, since some species of tree frogs (as well as other frogs) are able to survive freezing during cold winters. Ice crystals form within the bloodstream and tissues, solidifying its insides. In frog species where this occurs regularly, the animals accumulate urea in their tissues, but as Scorpius can enter a cryobiotic state at any time this is not the case. It probably does convert large amounts of liver glycogen to glucose similarly to frogs, in which this occurs as a response to ice crystallization. Using this glucose (and urea, if it produces enough normally), Scorpius can prevent cellular damage by limiting ice formation and retaining osmotic pressure in its cells. In wood frogs, which are famous for their cryobiotic abilities, about 45% of the body turns to ice and can remain that way for up to eleven days. The cardiovascular and respiratory systems cease to function, starting up again when the animal thaws. Survival is possible even if 65% of the body freezes. In Scorpius, this ability is taken to an extreme. Metabolic activity can be brought to a minimum for at least five years, likely indefinitely, and the body can survive being completely submerged in liquid nitrogen because it does not breathe while in stasis. It can recover from this state fairly quickly once temperatures normalize. In order to survive such an ordeal, it is likely that Dr. Wu engineered novel cryoprotectants for its body to use along with the urea, glucose, and antifreeze proteins utilized by naturally-occurring animals.

The way in which it moves its body suggests that it experiences constant pain. Over time, this distress probably contributes to its characteristic behavioral problems, eventually leading to the complete deterioration of its psychological health.


Hatchling stages have not been observed, but may be similar to Indominus. The subadult and adult stages have been observed directly; there appears to be no major difference in anatomy other than size. This is similar to Indominus, in which no specimens ever reached full adulthood.

Similar to Indominus, Scorpius experiences extremely rapid growth (whether it is facilitated by sepiid genes is not known at this time). It reaches its adult size in under four months. The total life expectancy is unknown, as none have ever been allowed to live into old age. Since it is plagued by numerous health issues owing to its unnatural anatomy and physiology, it is unlikely that any Scorpius would be very long-lived without human intervention.

Sexual Dimorphism

Male Scorpius rex do not naturally exist, since the species reproduces by gynogenesis. However, some other members of this hybrid’s lineage have had male specimens, so one could in theory be genetically engineered. The appearance of such a hypothetical male is not known.

Preferred Habitat

Since it is an artificial creature, it has no natural habitat. It was engineered to be adaptable, however, and is capable of surviving an extreme range of temperatures. While originally intended to live in a warm and humid tropical environment, it is capable of surviving ultra-cold conditions up to and including bodily freezing. A not-inconsiderable amount of its water mass can turn to ice without any ill effect, a situation it is able to survive possibly indefinitely. This would enable Scorpius to inhabit virtually any terrestrial climate. As an adept climber, it can also scale walls, trees, and other structures and access areas its competitors cannot. The main limiting factor for its survival is nutrition; such an active creature has an elevated need for food.

Isla Nublar

In April of 2008, Masrani Global Corporation and InGen authorized evolutionary geneticist Dr. Henry Wu to use his research into artificial hybridogenesis to create a new form of life for the Jurassic World theme park on Isla Nublar. The park had been suffering due to its extreme operating costs, and the Board of Directors believed that engineering a hybrid animal to showcase the company’s genetic power would attract more investors and visitors. Over the course of about a year, Dr. Wu used the techniques he had studied since the 1990s to develop the Scorpius rex, hatching it at an undisclosed date (possibly April 9, 2009 based on a now-deleted timeline entry on the Masrani Global website backdoor). It was developed and hatched in the field genetics laboratory, rather than the Hammond Creation Lab in the main park, to preserve its secrecy. Only one specimen was ever hatched, despite numerous experiments; E750 was the first and only success. The animal, a female, was kept contained in the laboratory while Dr. Wu and CEO Simon Masrani reviewed it. Masrani considered it too ugly for park exhibition, and Dr. Wu found that it was unpredictably aggressive. Following an incident in which it breached containment and attacked Dr. Wu to near-fatal effect, E750 was put into cryonic stasis in an expansion of the lab which was marked as “under construction.” It entered a state of cryobiosis sometime between 2009 and 2010, remaining alive but completely inactive.

Left eye of a mature S. rex

Isla Nublar was evacuated on December 22, 2015 due to the escape of a related hybrid dinosaur, the Indominus rex, which Dr. Wu had engineered as an improved version of the Scorpius. Although power to the park was deactivated, a backup generator ensured that E750 would remain frozen. Six to eight weeks after the park closed, a power overload caused the cryonic containment to shut down, and infrastructural damage to the park’s electrical grid caused a system failure. This allowed E750 to thaw and revive. It forced its way out of the stasis tank and into the maintenance tunnels, eventually accessing the surface.

Sometime after its escape, it laid an egg, having fertilized itself through parthenogenesis. The egg hatched into a second female Scorpius. E750 probably did not care for its offspring, since they were seen to fight violently later, but the offspring did survive to adulthood.

Both Scorpius roamed the island, preying on any animals they could find and periodically fighting with one another in competition for resources. Their range encompassed Lookout Point in the west to the raptor paddock in the northeast, and at least as far north as the Northwest Dock. One of them ventured into the caves connected to the Jungle River in the east, and both were sighted near the Kon penthouse dock in the west. This also represented the southernmost confirmed extent of their range.

In June of 2016, six months after the park closed, the Scorpius encountered a group of six young parkgoers who had been left behind in the December evacuation. These youths were living at the ruins of Camp Cretaceous, which they had originally been brought to Isla Nublar to experience, and had rebuilt into a makeshift home; E750 was the first to encounter them, but was drawn away by the call of its offspring. It envenomated one of the campers, who was saved using antivenom developed by Dr. Wu’s biology staff. Due to the threat posed by the Scorpius reproducing, the campers developed a plan to tranquilize and kill both of them. This occurred at the ruins of the Jurassic Park Visitors’ Centre, though it did not go as planned; rather than tranquilizing the animals, the building was rigged to collapse. At least one of the Scorpius was confirmed dead, and none have been seen since, suggesting that they were both indeed crushed to death.

It is unknown whether E750 or its offspring had reproduced again prior to their deaths.

Isla Sorna

This species is not known to have been introduced to Isla Sorna.


While it could survive nearly anywhere on land so long as food is available, no Scorpius rex has yet been confirmed in an environment outside of Isla Nublar.

Behavior and Ecology
Activity Patterns

It is impossible to predict whether Scorpius will or will not be active at any given time. Like its natural predecessors, it is highly capable of seeing in dark conditions, and it also has the ability to sense thermal radiation. This makes it fully capable of navigating by night as well as in the daytime. Scorpius has been sighted active at various times of day without any clear pattern. It does rest, entering inactive docile states when at peace, but is easily triggered into an active state by virtually any stimulus at all. Once active, it spends every moment either hunting, eating, or in territorial combat with others of its kind.

Diet and Feeding Behavior

Like its relatives and constituent species, Scorpius rex is a carnivore, and such an active animal requires huge amounts of food to sustain itself. Its rapacious appetite is a trait it shares with Indoraptor, but not Indominus. However, like Indominus it frequently engages in surplus killing. The difference here is that while Indominus kills for an adrenaline rush, Scorpius stashes its kills to eat later.

Its dark coloration and climbing abilities make Scorpius rex an efficient ambush hunter.

It can adapt its hunting style to the type of prey it is going after, attacking swifter targets by ambush while chasing down larger, slower victims. While it is not as fast as Indoraptor, it is still a fairly quick animal and can accelerate very rapidly to its top speed. When ambushing fast prey such as Gallimimus, it will launch itself into a pounce just as it reaches its maximum speed, propelling itself through the air and using its momentum to reach a speed faster than it is capable of running. It impacts its prey headfirst, using its jaws and hands to pin the prey down. However, it rarely uses its teeth or claws to make a killing strike; instead, it utilizes its venomous spines. Those located on the tail seem to be its preferred weapons, and the tail is highly flexible as to sting prey from any angle.

The spines are sharp and bony, with those on the dorsal side being the most complex and most deadly. All of its spines are derived from scorpionfish fins, possessing mucus glands at their bases that secrete a poisonous fluid which coats the spines. On its dorsal side, the spines are homologous to the pterygiophores of a fish’s dorsal fin. Each pterygiophore consists of a basal and a radial component. The radial is the visible part of the spine, and in Scorpius, it is designed to detach once embedded in a prey item. Once the skin is punctured, the venomous mucus enters the bloodstream and quickly spreads around the body, leading to nausea, fatigue, and disorientation. These symptoms become increasingly severe the longer the venom circulates, and occurs more quickly in smaller victims or if multiple spines become embedded. In larger victims, the symptoms may abate if the spines are removed, but smaller prey items will not recover without medical intervention. Humans are extremely vulnerable to this because of their small size and soft, unprotected skin; death may occur within an hour. Envenomation leads to respiratory failure and then cardiac arrest. It can grow the spines back in relatively short order, meaning it probably requires a lot of calcium in its diet.

A Ceratosaurus killed by Scorpius envenomation (note the spines embedded in the neck)

Larger prey items are harder to bring down; a Sinoceratops suffering from single-puncture envenomation of the tail was able to get back on its feet when the barb was removed, showing signs of pending recovery. However, an extremely large victim may be surprisingly easy to kill. An adult Brachiosaurus was seen to collapse after being envenomated and having one of its legs give out. For such a huge creature, falling down (especially among trees and boulders) could lead to serious injury or death. Scorpius can also benefit from fortuitous accidents among its prey; it often causes panic when it attacks, and animals may become injured in stampedes. Young animals can also be left behind in the panic, giving it an easy meal. Like all carnivores, it prefers to eat with as little trouble as possible, so it usually goes after the most vulnerable prey; it commonly eats Parasaurolophus, having driven this hadrosaur’s population levels very low during the five months it was active on Isla Nublar. It also preyed upon Ouranosaurus, and the fairly non-aggressive theropod Ceratosaurus.

Scorpius may occasionally kill prey using its teeth or claws, including the highly curved raptorial claws of its feet. Once its prey is dead or incapacitated, it will either eat it where it has fallen or drag it somewhere to eat later. Since it is a strong climber, it may haul the carcasses of its prey into trees where competitors cannot reach. Spines are sometimes left embedded in the bark of trees where it has cached food, possibly as a territorial marker or as a way of reminding itself where its food is stashed. Since the spines are coated in venomous mucus, it is dangerous to touch them, which can also deter other carnivorous species from stealing its food.

Along with its high metabolic needs, Scorpius is perpetually prepared to enter a cryobiotic state, which likely influences its diet. Cryoprotectants are vital to the survival of a frozen animal, and glucose is a common one; antifreeze proteins and urea are also used by many animals capable of cryobiosis. Part of the reason Scorpius eats so often is likely to remain prepared for cryobiosis at any given moment. Its malformed anatomy suggests that it is in pain whenever it moves; cryobiosis is probably the only peace it will ever know, and this may motivate its hyperactive diet.

Social Behavior

The one thing Scorpius rex seems to dislike above all else is its own kind, even including its immediate family. It will respond to the vocalizations of other Scorpius by abandoning whatever it is doing and making for the rival right away, challenging and fighting with it. Whether these fights are motivated by territory, competition for resources, or more complicated psychological reasons, a Scorpius will prioritize fighting a rival over any of its other needs or wants, including the presence of rivals belonging to other species.

Intraspecific combat in Scorpius rex

When it encounters a conspecific rival, it will first try to intimidate by screeching, gaping its jaws, and making exaggerated gestures with its arms. So far only two Scorpius have been observed and neither one ever backed down from combat before blows had been exchanged. If the initial intimidation challenge fails, the animals will launch at one another and fight viciously. Tactics include biting, clawing with the arms, kicking with the legs, and stinging with the tail; using the spines is ineffective against other Scorpius as they are immune to the venom, but a sting is still painful. The spines of the arms and legs appear to be used as weapons in intraspecific combat rather than as hunting implements; they can be used to jab and stick a rival, similar to the spines of the tail. The spines on the head are likely defensive, discouraging a bite to the skull from a rival.

Despite the savagery with which they fight one another, it does not appear that Scorpius rex kill each other in intraspecific combat very often. In early 2016, specimen E750 and its offspring fought on several occasions, but both always came away from these clashes more or less unharmed. It is unknown what precipitates the end of a fight other than both animals simply exhausting themselves and leaving to regain energy.

It is intelligent, but not to the degree of its descendants Indominus and Indoraptor. Even one of its progenitor species, Velociraptor antirrhopus, exceeds it; Scorpius has been witnessed failing to figure out how to operate a door handle, a simple puzzle which multiple Velociraptors have solved.


Details are scarce about just how Scorpius rex reproduces, but it is noteworthy for being the only member of its lineage to have successfully bred in the wild. Only one female was ever hatched under laboratory conditions, but it was able to reproduce asexually. Darius Bowman hypothesized in 2016 that this parthenogenic reproduction was possible due to genes incorporated into the Scorpius genome from tree frogs (possibly inspired by the fact that unplanned breeding in Dr. Wu’s specimens had been enabled by tree frog genes before). Parthenogenesis is more common among water frogs, but tree frogs may possess the prerequisite genes for this process to occur.

In the wild, two closely-related frog species may produce hybrid offspring which constitute a new, third species. Since these hybrid frogs are all female, they cannot reproduce sexually with one another. Instead, they mate with one of the species that originated them. Parthenogenic frogs utilize one of two methods to reproduce: gynogenesis and hybridogenesis. These are very similar, differing only in which stage the male’s DNA is discarded. In gynogenesis, the sperm of the male will prick the female’s egg cell, but does not penetrate. This triggers the egg to begin dividing as though it has been fertilized, doubling its number of chromosomes without incorporating the paternal genes. In hybridogenesis, the male’s DNA is actually utilized, but is abandoned partway through the cellular replication process, with only the female’s DNA being passed on to the next generation. As a result, the offspring are clones or nearly clones of the parents. These method of reproduction brings the disadvantages of both sexual and asexual reproduction and the advantages of neither, and so is uncommon.

Regardless of whether Scorpius rex reproduces using gynogenesis or hybridogenesis, if it does indeed reproduce in the manner of unisexual frogs it must mate with a related species in order to breed. This hybrid animal possesses DNA from a wide range of theropods including the families Tyrannosauridae, Dromaeosauridae, Abelisauridae, and possibly others. It could mate with the males of many possible theropod species because of this; anything within the clade Averostra could be a potential mate. Nearly all species of de-extinct theropod are classified within this range, with only the more primitive theropods such as Dilophosaurus falling outside of it.

However, the behaviors and appearance of Scorpius rex make it unlikely that any theropod species would view it as a desirable mate. It does not closely resemble any naturally-occurring dinosaur species, and its wanton aggression toward virtually any living thing it encounters would frighten away most potential mates. Here, the venom of the Scorpius may serve a purpose beyond simply killing prey. By incapacitating a male theropod, Scorpius could obtain itself an unwilling (and soon to be deceased) participant in its asexual reproductive process. Since the male’s DNA would be either destroyed or abandoned during reproduction, his genes would not pass on into the next generation. Instead, he would die in the service of creating another Scorpius with no benefit to himself, dying while disoriented and in pain. It is likely that the predatory Scorpius eats its newly-dead mates, using the protein from their meat to aid in the formation of eggs and the growth of offspring.

The egg-laying process itself has never been observed, so these behaviors are completely unknown. In parthenogenic amphibians, the embryonic mortality rate is very high; the Scorpius specimen E750 is only known to have produced a single viable offspring which survived to adulthood. Generally, theropod eggs are oblong, and medium-sized dinosaurs hatch after around six months, but this is not the case for Scorpius. An egg of this species laid sometime during or after February 2016 had hatched, and the offspring grown to full maturity, by June of the same year. This species is almost unarguably the worst parent in all of Dinosauria, and one of the worst animal parents in general; beyond simply not caring for its offspring, it will actively track down and violently fight its offspring once they are both mature. As stated previously, the maturation process is extremely rapid, with conception to adulthood occurring in less than four months.

Offspring produced through parthenogenesis may look different from their parents, mostly in terms of coloration. Whether this is due to internal genetic recombination, epigenetic factors, or non-genetic influences such as diet or health has not yet been confirmed.


Scorpius rex experiences few sensations aside from distress and frustration, so most of its communication consists of angry or otherwise aggressive signals. In human terms, most of its calls are a form of emotional venting. Its vocalizations are similar to those of its relative Indominus rex, with a range of screeches, hisses, yowls, and roars being heard; it often cries at a very high volume. When agitated, it may emit ear-shattering screams which can be painful to other animals. While victims are recovering from this auditory assault, the Scorpius can use their disorientation and shock to move around unnoticed.

Most of its vocalizations are for its own benefit, expressing its discomfort and consternation, or for intimidating and frightening other creatures. But it does communicate with its own kind, albeit only for aggressive reasons. If one Scorpius hears the cries of another, it will take this as a challenge. Abandoning whatever it is doing, it will head straight for this rival and engage it. These fights involve posturing and intimidation displays which precede the physical combat; methods of intimidation include loud screams and roars, gaping the jaw to display the large teeth, and contorting the arms into bizarre positions (this might be a way to show off their flexibility). These forms of body language are also used against rivals belonging to other species, including humans. Unlike the similar Indoraptor, the bodily ornamentation does not appear to serve a communicative purpose. The quills of Indoraptor can be raised and lowered to express mood, but the rigid bony spines of Scorpius are far less mobile.

Ecological Interactions

There is no known natural ecology for Scorpius rex, as it is an artificially-engineered species.

Possibly due to the ceaseless pain caused by its malformed anatomy, this dinosaur is highly aggressive toward virtually every living thing it encounters, attacking whenever it is disturbed. It may not always eat its victims, but since it stashes food away where other animals cannot reach it, these surplus killings might be a means of storing food for later. Since it is reasonably fast, it can run down prey such as Parasaurolophus and Ouranosaurus; for others, such as the speedy Gallimimus and predatory Ceratosaurus, it prefers a swift ambush.

Scorpius feeding on a freshly-killed Parasaurolophus

Larger victims require more venom to fell. A single spine can eventually cause enough fatigue in a medium-to-large animal to be potentially lethal, but if removed in time, the spine will not deliver the full load of venomous mucus to cause death. For example, a single spine stung into the tail-tip of a Sinoceratops had caused the ceratopsian to collapse with exhaustion, but removing the spine caused the dinosaur to get up in shock and react aggressively. It was able to walk away on this sudden rush of adrenaline, and may have recovered. Another Sinoceratops was less lucky, having been observed colliding head-on with a boulder while running in a panicked stampede. This impact may have resulted in a disabling head injury, which would be a death sentence to a wild animal. A serious enough head injury could have been fatal on its own.

The largest prey item it has been known to kill is the gigantic Brachiosaurus. To kill this sauropod with venom alone, a huge quantity would be needed, but the venom is not actually what causes this dinosaur’s death. Instead, its sheer size is literally its downfall. If stung in one of its legs, sudden muscle fatigue can cause the brachiosaur to collapse from a standing position. From such a height, striking the ground could break its neck or skull, especially if it lands on uneven ground or debris. This can cause fatal injuries and death.

When it enters an environment, the presence of Scorpius rex is a disruptive influence and behavioral changes are observed in other animal species. This dinosaur was accidentally let loose onto Isla Nublar in early 2016, and over the course of the next few months other animals altered their behavior patterns. Some of the dinosaurs abandoned their previous habitats in search of safer places to live; notable examples were Compsognathus and a bioluminescent variant of Parasaurolophus. In other species, heightened aggression was noted. Ouranosaurus showed uncharacteristically hostile behaviors after being hunted, ramming vehicles and objects without provocation and treating humans as serious threats. They were also among the species which established new territories, selecting a harbor area that lacked the environmental features they normally preferred. Brachiosaurus did not show aggression, but exhibited signs of anxiety. They trampled the plant life they fed upon, and in one case a mother unintentionally left her offspring behind. The small theropod Monolophosaurus, which is typically solitary, was observed to begin congregating in larger groups for protection and also became unusually aggressive toward other animals. Heightened combativeness was also seen in Stegosaurus. Among non-dinosaurian animals, Pteranodon was observed becoming active at night, when it is normally diurnal.

The only dinosaur which seems unbothered by the presence of Scorpius is the well-defended Ankylosaurus. While this dinosaur can be killed by the larger Indominus rex, it is big enough to fend off a Scorpius. Furthermore, its armored body provides protection against the venomous spines. So long as it keeps its less protected underside out of the tail’s range, it can deflect spines and avoid being stung. Ankylosaurus is the only animal that a Scorpius rex has been confirmed to back down from, actually giving up the hunt rather than try again. It has also ignored a combative Velociraptor, but this was due to being involved in an intraspecific fight at the time; clashing with its own kind is always a higher priority. No animals are known to prey on this species, as it is probably poisonous when eaten.

Few ecological benefits come from Scorpius rex. It is an insatiable predator, a sexual parasite, and a generally disagreeable creature which expresses only malice toward other living things. The only creatures that would benefit from its presence are scavengers small enough to escape its notice and feast upon the carnage it creates. Once introduced to an ecosystem, it will decimate the populations of other animals (it drove Parasaurolophus close to extinction on Isla Nublar and may have directly caused the extinction of Certaosaurus). Because it often drags its victims’ carcasses into trees, any food it does not eat has the potential to fertilize the ground near where it is stored. Scorpius can unintentionally and indirectly benefit plant life as well as soil-dwelling decomposers in this way. It benefits from the forest too, its dark coloration helping it hide among tree branches and foliage. An excellent climber, it can navigate forest canopies and ambush prey from above. Spines embedded within trees do not appear to have any harmful effect. It is possible that these spines may be embedded intentionally, since they are sometimes seen in the bark of trees that the Scorpius has stored food in; they may be markers or a means to discourage other animals from stealing its food.

Cultural Significance

When it was first conceived, the Scorpius was meant to symbolize the genetic power InGen had achieved. This was the first successful attempt by Dr. Henry Wu to engineer a new animal species via genetic hybridization, and to him, the Scorpius represented his personal accomplishment rather than just InGen’s. Before long, however, its symbolic meaning took a turn for the worse. While the animal’s unsightly appearance made it unsuitable for exhibition in Jurassic World, its body was in constant pain and this led to psychological deterioration. Eventually, the animal reached a point where it could be triggered into an aggressive state by nearly any stimulus, no matter how minor. Wu himself was attacked and envenomated once, leading to his decision to put the specimen in cryonic stasis for research. He did not comply with orders to euthanize it.

Scorpius was a frustrating reminder to Wu of his failures, but Wu always maintained that failures can be just as valuable as successes. Throughout his career he has used mistakes and unfortunate consequences as tools to build better in subsequent attempts. In this case, his next attempt was the Indominus rex, which exceeded his expectations. By that time, he was no longer just engineering for the park; he had now branched out toward other fields, particularly the military applications of genetics. The E750 specimen remained in a cryopreservation tank, rejected by its creator and the company that had funded it. Not until 2016 was it rediscovered, having been kept a secret from all but Wu’s most trusted staff, and from that point it came to symbolize the consequences of unchecked hubris.

In Captivity

Although it has never been exhibited to the public, Scorpius rex has the dubious honor of being the longest-lived member of its lineage, remaining (technically) in captivity for about seven years. A minimum of five of these years were spent in a state of cryobiosis, induced by cryonic stasis technology utilized by Dr. Henry Wu and his staff. This procedure was initiated following an incident in which the animal broke out of its containment and attacked Dr. Wu, envenomating him; he had already developed an antivenom, and his staff members saved him with it.

Creating a Scorpius rex on purpose, now that its physiology is known, is highly unethical. As the first attempt at making an animal hybrid, its traits are mismatched and it experiences continuous distress. Its every movement causes it pain; its breathing is labored due to its brachycephaly, much like dog breeds such as pugs. Over time, it becomes increasingly sensitive to stimuli and will lash out if disturbed, despite experiencing periods of seemingly docile inactivity. No medication has thus far been designed for alleviating its health issues, and some such as its breathing difficulties may be untreatable. Realistically, the only way to keep this animal in captivity is to induce cryobiosis, containing it within a chamber cooled to below the freezing point of water. This will turn most of the creature’s body water to ice and suspend its metabolic processes. It can remain in this state indefinitely, but will quickly become active again if thawed. Being frozen probably renders it unconscious, meaning that cryobiosis allows it to live without being constantly in pain. Keeping it alive in any other state of existence is simply cruel.


The creation of Scorpius rex in 2009 was a major step forward in genetic science research, this being the first animal created via artificial genetic hybridization. This scientific technique was developed by Dr. Henry Wu and his staff, working for International Genetic Technologies. Prior to Scorpius, the first hybrid organism created using Dr. Wu’s methods was a flowering plant, Karacosis wutansis, which he created in 1997. Applying these methods to animal biology would have required the development of new genetic engineering techniques and technologies, as well as increased knowledge about the sourced genomes.

While not all of the genomes used to build this hybrid were fully sequenced at the time (the Velociraptor genome, for example, was sequenced in 2012), all of the genes used to create it would have had to have been identified, since their function would be transferred into the new animal. Not all of the genes utilized resulted in the expected biological traits, though. For example, genes sourced from tree frogs (most likely used to enable the Scorpius to adjust to a tropical climate, like its descendant Indominus) unintentionally allowed it to reproduce parthenogenetically. This trait is more often seen in water frogs, rather than tree frogs; it appears that tree frogs do possess the prerequisite genes for parthenogenesis even if they do not exhibit the phenomenon themselves.

Overall, the Scorpius rex was deemed a failure. Firstly, its appearance was considered unappealing, so its usefulness as a park attraction was highly reduced. More serious issues came later; Dr. Wu had known it would be venomous and this trait was intentional, but its behavior became erratic as the animal developed psychological problems. As the first of its kind, there was no precedent for how to deal with its health. Its anatomy caused it constant pain so long as it was conscious, and this led to the degradation of its mental health as well. Eventually it existed in a perpetually-anguished state and frequently lashed out at Dr. Wu and his researchers. An antivenom was developed, probably based on the scorpionfish antivenoms used commonly in Australia. It was proven effective in a real-life scenario when Dr. Wu himself was envenomated, being saved by his research staff who administered the medicine quickly.

Although it was put into cryopreservation and was never intended for release, Scorpius formed an important first step toward understanding artificial hybrid biology. Its health issues informed later researchers on how to better engineer an animal that would not be continuously harmed by its own body, though subsequent efforts universally failed to provide for the animals’ mental health. The behavioral problems of Scorpius rex did, however, provide useful insights into how genetics shapes animal behavior; it allowed Dr. Wu to reference this earlier failure while developing later genera such as Indominus rex (created in 2012) and Indoraptor (created in 2016).


Scorpius rex chiefly escaped controversy in the public eye due to its obscurity; few Masrani Global employees outside of Dr. Wu’s research staff at the field genetics lab knew of its existence. However, its creation and treatment do encompass a number of the issues surrounding genetic engineering, particularly the field of artificial hybridization. Much like when InGen first began bringing animals back from extinction, its biology was wholly conjecture in the initial stages since scientists had never observed it before. When specimen E750 matured, it experienced constant suffering due to the malformation of its body parts and internal anatomy. These health issues went largely unaddressed, as InGen scientists would have had no way of knowing what its “proper” health would have looked like. Its psychological well-being suffered as a result, no doubt compounded by being kept in containment.

Dr. Wu does not seem to have linked E750’s mental state with its physical ailments, with his reports implying that he instead believed that the psychological issues were an unwanted byproduct of the hybridization process. His neglect for considering alternative explanations likely worsened E750’s condition. The specimen was rejected by all Masrani Global staff members, with the company’s CEO ordering its termination; previously it had been deemed unfit for park exhibition due to its ghastly appearance. Wu did not euthanize it, but rather put it into cryopreservation for further research. While this rendered E750 unconscious in a cryobiotic state, it inadvertently gave the specimen the only peace it would ever know.

After the failure of its containment unit roughly two months after the closure of Jurassic World, it was reawakened and allowed to enter Isla Nublar’s ecosystem unsupervised. At the time, the only humans on the island were six youths who had been accidentally abandoned during the evacuation of Jurassic World. E750 attacked them on a few occasions after they discovered its existence, including one incident in which one of the teenagers was envenomated and came close to death before receiving the antivenom. In order to not only protect themselves but also prevent further harm to the rest of the island’s animal population, the group’s leader Darius Bowman planned to tranquilize both E750 and its offspring so that they could be killed. While the plan did not go quite as intended, they did succeed in killing the creatures.

There was never any consideration given to humane ways of treating the Scorpius; it was explicitly called a monster, not only by the people involved with the events of 2016 but by at least one member of Dr. Wu’s own staff. Wu himself considered it useless other than its potential as a guideline for what not to do in the future.


Originally, Masrani Global Corporation’s Board of Directors had authorized geneticist Dr. Henry Wu to create a hybrid animal in order to attract new investors and customers to offset Jurassic World’s extremely high operating costs. What manner of exhibit it would have been housed in is unknown, since it never reached the approval stage. Its appearance was deemed unattractive by CEO Simon Masrani, and after the specimen attacked Dr. Henry Wu, it was ordered to be euthanized. Wu did not comply with company orders and kept it alive in cryopreservation for further study without his employer’s knowledge.

Aside from its value as a research specimen, not much study has gone into the resources that can be obtained from Scorpius rex. Most de-extinct life forms are sources of biopharmaceutical products not available from modern organisms, and as engineered hybrids have biology even more unique, they probably yield unprecedented medicines. However, the only medical product thus far obtained from Scorpius is its antivenom. Since its venom is derived from the genetic pathways in fish of the family Scorpaenidae, it has precedent in the natural world, and the antivenoms used for scorpionfish stings probably presented a stating point for Dr. Wu’s researchers. It is also possible that the development of a Scorpius antivenom could have led to new developments in scorpionfish antivenom.

The descendants of this animal, Indominus rex and Indoraptor, were engineered specifically as military animals (though both failed to meet the requirements for performance as such). Scorpius was not built for this purpose, and its numerous maladaptive behaviors and other health issues make it completely unsuitable for training. In fact, it has little use in captivity whatsoever. While a mercenary team hired by Wu’s later employer Eli Mills considered capturing a Scorpius specimen (with team leader Hawkes suggesting it would fetch a high price), Wu described the hybrid as enough of a failure to make it worthless even on the black market.

Scorpius can also damage technology because it responds to any moving objects as though they are animals, making it an economically significant pest. It has been known to attack and destroy small drones. Should one end up in an environment where people live, it could threaten humans and domestic animals such as livestock, making it even more economically damaging. To keep it contained would require the continuous use of a cryopreservation tank, which is expensive and needs regular upkeep; simply put, keeping this animal alive is very costly and difficult to justify.


While there is evidence to suggest this animal has gone extinct, we cannot rule out the possibility that more might exist somewhere (after all, the existence of more than one was totally unexpected, yet two were witnessed on Isla Nublar in 2016). Scorpius rex is unpredictable, even when compared to its descendants Indominus and Indoraptor; these later hybrids are practically normal animals next to Scorpius. Being familiar with the hunting and attack patterns of more recent hybrids will not prepare one for the chaos incarnate that Scorpius rex represents.

When it comes to fighting off this creature, a good defense is the best offense. Unlike specimens of Indominus and Indoraptor that have been observed, Scorpius does not hunt humans in particular but rather will lash out at anything within its range, so do not go looking for conflict. Instead, be prepared to fall within its indiscriminate line of fire and defend yourself until something distracts it. Any means of protection should be on the table: its attacks may include slashing with its hands, kicking with its legs, pouncing and biting, and ear-splitting screeches that can disorient you. If one has been sighted, remain in the open where you can see it coming. It is an adept climber, and often it will attack prey from above. Its dark coloration helps it blend in with shadowy canopies, especially at night. Stay away from dense tree cover or thick forests where it can more easily ambush you. Take cover within small spaces where it will have trouble following, but bear in mind how strong it is; plaster, wood, and aluminum will not stop its attacks. Should it set its sights on you, the only good shelter is an extremely sturdy one with room enough for you to stay out of reach.

Its most dangerous weapon is its tail, unlike most carnivorous dinosaurs. When attacking, it will lash its flexible tail to one side or the other, attempting to sting any vulnerable skin with its venomous spines. Blocking these by any means possible will save your life. Should one become embedded in your clothing or equipment, be cautious while removing it that you do not puncture your skin; the mucus coating the spines is the source of the venom. Should a puncture wound occur, remove the spine as quickly and safely as possible (we recommend using gloves, in the event that you have any other injuries from the fight). The longer the spine remains embedded, the more venom will be administered, decreasing your chances of survival. Once the spine is removed, apply heat to the wound. Scorpionfish stings can be treated with water at temperatures of up to 113 °F (45 °C), but no hotter; the venom can be denatured by this kind of heat. The pain can be lessened with the use of vinegar. However, this has not yet been tested with Scorpius venom, and it may not be as effective. The only other hope for recovery lies in the antivenom, developed in 2009 by International Genetic Technologies. Unfortunately, since this creature was bred in a classified project and was supposed to have been terminated, the antivenom has not been in production for over ten years. If you live in a country where scorpionfish stings occur, such as Australia, you may try a scorpionfish antivenom. The amount of antivenom necessary will depend on the number of punctures. After the antivenom is administered, some symptoms such as nausea may persist for an hour or more, but will eventually dissipate. Should Scorpius turn out not to be extinct, it will be the responsibility of the medical community to make antivenom available to people in affected areas.

If you are attacked by this animal, the easiest way to end the conflict is a distraction. It can sense thermal energy, which allows it to track prey down in total darkness, but this also gives it a weakness. Like any sense, thermal sensing can be fooled, and Scorpius is known to be easily captivated by fire and other sources of high heat. You may also try to administer any kind of painful stimulus; this dinosaur’s unfortunate anatomical configuration already causes it neverending distress and it will naturally want to avoid anything that makes it even more pained. Alternatively, you may try the carrot rather than the stick: present it with something that it wants more than you, for example a larger and more satisfying prey item. Finally, if multiple Scorpius are nearby, make them aware of one another. There is nothing they apparently hate more than their own kind, and so they will abandon you in order to brawl. While they are distracted fighting their kin, you will have a chance to get away, or to eliminate the threat if you have the means to do so. There are few creatures that we really recommend exterminating, but Scorpius rex was engineered to be exceedingly dangerous. If not dealt with, it can cause severe damage to local ecosystems, and to you personally. Means to contain it are few and methods to alleviate its suffering even fewer. Pity it if you are so inclined, but do not neglect to protect yourself and the other living things in your community.

Behind the Scenes

While Jurassic World: Camp Cretaceous did not originally plan to include hybrid species other than the first season’s Indominus, the decision to include this creature was eventually reached as the writers could not pass up the opportunity to show a more tragic and tortured hybrid. Both the Indominus and Indoraptor had originally been conceived as pitiable monsters rather than simply frightening antagonists, but later revisions to the stories of both Jurassic World and Jurassic World: Fallen Kingdom simplified their roles and made them unambiguously villainous. The inclusion of two different Scorpius which fight one another is also a reference to the first two Jurassic World trilogy films: the Indominus was said to have cannibalized a sibling which does not appear in the film, and the Indoraptor was planned to have a sibling at one point as well which it would eventually fight. Camp Cretaceous was the first film-canon installment to actually show this conflict.

DreamWorks Animation and Mattel, Inc. consistently misspell Scorpius as “Scorpios,” while the misspelling “Scopius” is less common. Many fans believe “Scorpios” to be the correct spelling as it appears on DreamWorks social media and Mattel toy packaging. However, the creators of Jurassic World: Camp Cretaceous (including showrunner Zack Stentz) generally spell it as Scorpius, and as they were the ones who created and named it, Jurassic-Pedia assumes that their spelling is the correct one.

Notable Individuals

E750 – First specimen of Scorpius ever bred, as well as its offspring