Due to Saurian being in early access and the lack of a publicly available official list of fauna planned to appear in-game, the roster of this page is not finalized and animals may be added or removed depending on what the developers decide to reveal is confirmed or not. That said, everything below has been at least mentioned as a potential inclusion — those unconfirmed will be explicitly noted — and it should be noted that such ambiguity mostly applies to smaller non-[non-avian] dinosaur species.
Also note that all profile images show the animals as currently in-game or planned for implementation. Due to Science Marches On, some of these designs are already outdated and updated versions have already been made and in most cases, publicized.
Playable Dinosaurs
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Dakotaraptor steini
Length: 5.5 meters
Mass: 300-350 kg
Current status: Main four life stages are in-game and playable.
A large dromaeosaur discovered in 2005 but only described in 2015. Juveniles are capable of limited flight.- Angry Dance: The threat display, which has been noted by some players as seeming less intimidating and more like a mating dance.
- Artistic License – Paleontology: While it is possible that Dakotaraptor were neglectful parents, their tendency in-game to cannibalize their own offspring is highly unlikely. Adults might consume their own children if starving, but they have no reason to do so when other foods are more easily accessible. However, the makers of the game most likely know this, and simply put it in to stop players from being silly and biting their parents.
- Brought Down to Badass: Downplayed; Dakotaraptor will lose its ability to fly when it becomes an adult, but it'll gain the ability to take on larger prey than before.
- Combination Attack: Older Dakotaraptor will sometimes team up to take down larger prey animals.
- Corporal Punishment: To avert player silliness, Dakotaraptor parents are quite intolerant of being bitten by their babies, which usually leads to them Offing the Offspring.
- Eaten Alive: While using "raptor prey restraint" (RPR) it'll take bites out of its prey and eat mid-grapple while it's still alive.
- Egg Sitting: A literal example. Dakotaraptor is the only playable (alongside Anzu) that will actively incubate its eggs by sitting on its nest.
- Feathered Fiend: Fully feathered like a bird, and fairly frightening.
- Fragile Speedster: Dakotaraptor are this for most of their lives until late in adulthood, being one of the fastest animals in the game but unable to withstand substantial injury from similarly-sized opponents.
- From Nobody to Nightmare: Babies are tiny and fluffy, vulnerable to attack from larger predators (including their own kind). As adults, they're formidable hunters.
- Grapple Move: Can latch onto other dinosaurs by jumping on them. This allows it to attack them without fear of retaliation, but you have to fight to stay on the animal.
- I'm a Humanitarian: Quite willing to prey on its own kind.
- Lightning Bruiser: Once it becomes fully mature, it goes from being a Fragile Speedster to being this. The super-adults are the second-largest terrestrial predators in the setting (only T. rex is bigger), can run extremely fast, and bring down prey much larger than themselves.
- Magikarp Power: RPR in a nutshell. You only gain it when you become a juvenile, and at that point it can only be used effectively on Acheroraptor. Combined with the need to fight to stay on your prey, it can take some getting used to. Once you master it though, you can take down a Triceratops as a super-adult with enough persistence.
- Noble Bird of Prey: Its design clearly takes quite a bit of inspiration from present-day accipitrids (namely the osprey and northern goshawk).
- Not Quite Flight: The juveniles can parachute-glide down from trees using their short, broad wings.
- Parental Neglect: While the hatchlings bond with their parents, the parents do not bond with the hatchlings or each other. The parents offer some protection to their young, but will abandon them if faced with a foe they can't defeat.
- Pint-Sized Powerhouse: Relatively speaking, as Dakotaraptor is an estimated 18 feet long. It's one of the smaller dinosaurs on the playable roster (only female Anzu are truly smaller, while Pachycephalosaurus and male Anzu are similar in size), but it can bring down prey the size of a Triceratops with enough skill and persistence.
- Press X to Not Die: How you stay on another dinosaur when using Raptor Prey Restraint.
- Raptor Attack: Averted at every turn. It's fully feathered (complete with wings!) and has many other accurate qualities, like tree climbing skills. The dev team also mentioned that they deliberately wouldn't portray the animal as a pack-hunter as they believed it to be overdone and too fanciful.
- Red Eyes, Take Warning: Its design features orange-red owl-like eyes with rounded pupils.
- Ridiculously Cute Critter: The babies are adorable!
- Series Mascot: Has more or less become this for Saurian. It was the first playable dinosaur, and is featured in most of the game's promotional media.
- Tree Cover: Hatchlings and juveniles can climb trees to escape from most predators.
- Tree Trunk Tour: A downplayed example. Hatchlings and juveniles can not only climb tree trunks but also perch and freely move around on branches, making for amusing side adventures if terrestrial gameplay gets boring.
- Useless Bystander Parent: Dakotaraptor parents will generally not bat an eye as their offspring commit fratricide/cannibalism, nor when one parent institutes their deadly form of discipline.
- Watch Out for That Tree!: Played with. When gliding, players can land on the trunks of other trees and resume climbing as normal, but can still crash into branches.
Pachycephalosaurus wyomingensis
Adult male
Length: 4.5 meters
Mass: 450 kg
Current status: Adult males are in-game as A.I.
A medium-sized ornithischian known for its thick domed head.- Battle Couple: Dakotaraptor players often find themselves being tag-teamed by mated pairs of Pachycephalosaurus.
- Battle Cry: Downplayed. It's a subtle chuffing sound that can be easy to miss, but if you hear it you know there's an angry Pachycephalosaurus about to run something down — just make sure it's not you.
- Hair-Trigger Temper: Described as "hardy and belligerent", they're very aggressive and willing to fight at the slightest provocation.
- Headbutting Pachy: They use their dome skulls as their main way of attacking, and males will engage in head and flank-butting contests. Subverted in that they don't ram each other like bighorn sheep as traditionally portrayed.
- Herbivores Are Friendly: Averted. It's probably one of the most aggressive dinosaurs in the game.
- I Have Many Names: Currently referred to as Pachycephalosaurus wyomingensis, but newer research indicates an anagenetic
shift occurred during the ~2 million-year period of Hell Creek's deposition, which would merit a different name for the animal represented in the last 300k years of the Late Cretaceous. (Possibly to Pachycephalosaurus spinifer due to the Two Aliases, One Character going on with Stygimoloch spinifer.) Notably the tie-in field guide refers to it as Pachycephalosaurus spinifer, suggesting its current designation in-game is planned to be updated. - One True Love: They mate for life and travel in pairs when partnered.
- Pint-Sized Powerhouse: Similar in linear dimensions to Dakotaraptor but much more heavily built, it can pack a punch with its bony domed head.
- Red and Black and Evil All Over: Can be seen as this by Dakotaraptor players given their red and (technically dark gray) color scheme and general propensity to threaten, attack, and relentlessly pursue players virtually on-sight. It doesn't help that their greater mass gives them an upper-hand in fights.
- Rule of Cool: The "pinecone" design of its tail, which appears to be inspired by that of Uromastyx lizards.
- Spikes of Villainy: The incoming redesign will probably add another level of intimidation for Dakotaraptor players.
- Two Aliases, One Character: Actually three going on for this dinosaur; the juveniles actually fall under a separate genus called Dracorex hogwartsia and the subadults actually belong to Stygimoloch spinifer, with only the adults being recognized as Pachycephalosaurus. However, Saurian follows the controversial (but currently unchallenged) proposal that that all three genera are the same animal at different stages of life.
- Use Your Head: Due to their thickly domed skulls, their main method of attack is headbutting.
Triceratops prorsus
Male ontogeny
Length: 8 meters
Mass: 9 tonnes
Current status: Main four life stages are in-game and playable.
The second most famous dinosaur of all time, known for being a rival of Tyrannosaurus rex.- Amazing Technicolor Wildlife: Simultaneously embraced and averted. Adult males are a golden-brown color and decked out with large bright golden spots with black outlines, and feature red heads with elaborate yellow markings on their frills that they develop throughout their growth. Females are far less elaborately colored, being various shades of brown and lacking frill patterns altogether. Hatchlings of both sexes are bright green with white spots.
- Battle Harem: As if not formidable enough on their own, female Triceratops travel in groups for mutual protection, often accompanied by their resident adult male.
- Chameleon Camouflage: Hatchlings are bright green with white spots to help hide them from the many predators who want to make a snack of them.
- Foil:
- To Anatosaurus, the other stereotypical Tyrannosaurus fodder in the game. Both are large, social herbivores that have vibrantly colored hatchlings and mature males, with drabber colored females. However, both have a spectacular number of differences:
- Triceratops lives in relatively small groups while Anatosaurus herds are quite large.
- Male Triceratops compete with each other for dominance of harems and forcibly evict rival males from their territory, while male Anatosaurus can coexist in herds.
- Triceratops is a permanent resident of the Hell Creek region while Anatosaurus is a migrant.
- Triceratops uses its head for defense via Horn Attack while Anatosaurus uses its large tail.
- Lastly, Triceratops is a playable dinosaur while Anatosaurus was relegated to NPC.
- Triceratops is also a foil to Ankylosaurus, the other playable large herbivore. Triceratops lives in herds while Ankylosaurus is solitary. Triceratops are also fairly common (though not as much as Anatosaurus or the ornithomimosaur) while Ankylosaurus is the rarest animal in the game. Ankylosaurus relies on its bony armor and clubbed tail for defense, while Triceratops defends itself via numbers and its horns. Additionally, Triceratops, at least at adulthood, is a Lightning Bruiser when charging and fairly fast when walking, while Ankylosaurus is a Mighty Glacier who cannot move fast period.
- To Anatosaurus, the other stereotypical Tyrannosaurus fodder in the game. Both are large, social herbivores that have vibrantly colored hatchlings and mature males, with drabber colored females. However, both have a spectacular number of differences:
- From Nobody to Nightmare: Baby Triceratops are vulnerable to attack, but as adults their large size, powerful beaks, and of course their horns, make them formidable creatures.
- Hair-Trigger Temper: They are quite territorial and will fight off any perceived threats.
- Harem Seeker: Adult males are normally solitary but will seek out and lay claim to any female groups in their territories, jealously defending them against other males.
- Horn Attack: Its main form of attack, unsurprisingly, is to gore opponents with its horns.
- Mama Bear: Mother Trikes are extremely protective of their young.
- One-Hit Kill: An adult Triceratops charge can instantly kill almost anything in the game.
- The Power of Trust: Triceratops live in small herds that need to work together to survive. In-game, you have a standing within whatever herd you belong to. It goes up when you warn them of threats and goes down from being a Jerkass (e.g. Crying Wolf, attacking herdmates). Doing so too often will eventually see you excommunicated.
- Rhino Rampage: Some of its behavior was unsurprisingly based on that of rhinoceroses.
- Sibling Team: Juveniles leave their natal herd and form their own herds with any surviving siblings.
- Temper-Ceratops: While females are sociable animals that live in herds and are protective of their young, males are solitary and only one of them is ever seen in a herd. Male Triceratops have to compete against one another and the game actively encourages you to do so, as players would have to fight against other males if it means patrolling a piece of land and mating with a female.
- Trampled Underfoot: Animals significantly smaller than the trike are outright killed by its charge attack, even if they are too short to be impaled on its horns, so it can be presumed they're simply trampled to death.
Tyrannosaurus rex
Length: 10-12 meters
Mass: 6-9 tonnes
Current status: Adults are in-game as A.I.
One of the largest theropods, and also the most famous dinosaur of all time. The undisputed top predator of the Hell Creek Formation, and a fierce hunter even as a hatchling.- Big Bad: When you're not playing as it, of course (and even then, you can't guarantee that another one won't try to kill you). It's the region's unrivaled apex predator and thus the most dangerous threat that you could end up facing. It's not evil though, just a predator.
- Chameleon Camouflage: Its dull brown feathers allow it to blend in with the forest while it's hunting.
- Feathered Fiend: If you're not playing as it, it's one of the most dangerous predators you can face, and it's fully feathered save for its lower body and tail. Averted with its current design, which is featherless.
- Fragile Speedster: Young Tyrannosaurus are this for most of their lives until late in adolescence when they bulk up and slow down. At their peak, adolescents are the fastest carnivores in the game and are able to run long distances to pursue prey.
- From Nobody to Nightmare: As a baby, it's a Ridiculously Cute Critter that is vulnerable to attack from larger animals (including its own kind). As an adult, it's the biggest, baddest predator of the region and has no natural enemies save for another Tyrannosaurus.
- I'm a Humanitarian: Adults will not above preying on their kind's own babies if they have to.
- Lighter and Softer: Its final design, compared to the original which resembled a Prehistoric Monster with red eyes and a dark black coat.
- Lightning Bruiser: Surprisingly nimble for its massive size and build, and among the most powerful and dangerous of dinosaurs in Hell Creek.
- Mighty Roar: Subverted. Dinosaurs likely didn't/couldn't roar like in the movies, but that doesn't prevent them from making loud scary sounds.
- Non-Malicious Monster: It's a predator that has to kill to survive and not out and out evil.
- Papa Wolf: In the game, fathers will care for the young just as males of most modern flightless birds do.
- Power Equals Rarity: Per the rules of actual population ecology, adult Tyrannosaurus (being the largest carnivores in the region) are among the rarest animals in the game, with many players only ever seeing a handful in a full several-hour play-through.
- Scary Teeth: Long, banana sized teeth with incredibly deep roots.
- Sibling Team: Provided they survive long enough, juveniles will stick together through adolescence after leaving their father's protection, only separating upon reaching adulthood.
- The Worf Effect: It doesn't matter how large and terrifying Tyrannosaurus is, it gets handily wrecked by a Mosasaurus if it wanders into its territory. Juvenile T. rex can be taken out by other predators such as Dakotaraptor.
Anzu wyliei
Adult male and female
Length: 4 meters
Mass: 250 kg
Current status: Adult male model is being animated
A large North American oviraptorosaur that is given the (completely speculative) ability to mimic the calls of other dinosaurs. One of two playables that were voted for by fans, alongside Ankylosaurus.- Amazing Technicolor Wildlife: The males are flamboyantly colored.
- Bizarre Sexual Dimorphism: The males are twice as large as the females and more colourful. For this reason, the two will have slightly different niches in the Hell Creek ecosystem.
- Eats Babies: Will occasionally eat eggs and baby dinosaurs.
- Egg Sitting: A literal example. Anzu is one of two playable species (alongside Dakotaraptor) that will actively incubate its eggs by sitting on its nest.
- Feathered Fiend: Less of a killer than the other predators, but still formidable, especially seeing as it's a Voice Changeling.
- Huge Guy, Tiny Girl: Anzu males tower over females of the species.
- Jack of All Trades: According to
Word of God it's in the middle of the road in terms of strength, speed, and power. - Mix-and-Match Critters: Described as a "turkey-parrot-emu" by many.
- Rule of Cool: Its mimicry ability, since there's no fossil evidence one way or another that it had it.
- Voice Changeling: Can mimic the calls of other dinosaurs.
Ankylosaurus magniventris
Adult male
Length: 5-8 meters
Mass: 4.5-7.5 tonnes
Current status: Adult male currently in-game as A.I.
A large and aggressively solitary dinosaur famous for its armored body and club tail. One of two playables that were voted for by fans, alongside Anzu.- Amazing Technicolor Wildlife: Downplayed. Adult males have bright yellow stripes on their head, scutes, and tail against a black head and upper body, similar to a box turtle. Females have similar patterns but with more muted hues.
- Beware My Stinger Tail: It has a club at the tip of its tail, which can easily break the bones of large predators and outright kill smaller ones.
- From Nobody to Nightmare: Baby Ankylosaurus will only be able to hide from predators due to their armor still forming. As adults, they are avoided by all predators other than Tyrannosaurus, which they can also defeat.
- Herbivores Are Friendly: Averted. They're jealously territorial against each other and other herbivores, and will fight back if a predator attacks them.
- I Work Alone: Is a largely solitary animal and fairly territorial.
- Mighty Glacier: Slow-moving, but has very strong armor and a powerful tail club.
- Tough Armored Dinosaur: A powerful and territorial ankylosaur.
- Xenophobic Herbivore: Adults at least are highly territorial and only tolerate each other during breeding season. They also defend choice food sources from other herbivores.
Non-playable dinosaurs and other creatures
Ornithischians
Anatosaurus annectens
Super-adult male
Length: 9-15 meters
Mass: 4-13 tonnes
Current status: Adult males and females are in-game
A very large hadrosaur that travels in herds and is a non-permanent resident of the local region. Lost the stretch goal playable vote to Ankylosaurus along with Denversaurus.- Amazing Technicolor Wildlife: The males have vibrantly colored heads and the babies are bright blue; female adults are much less colorful, as are fledglings. According to Word of God, the babies don't have to rely on camouflage as much as other baby dinosaurs because they're always protected by their massive parents; in fact, their bright coloration is an in-universe adaptation to prevent them from being stepped on.
- The Big Guy: One of the biggest creatures in the region.
- Gentle Giant: Are nonagressive most of the time, though it's certainly big enough to intimidate most predators in the ecosystem.
- I Have Many Names: Despite its "proper" genus name being Edmontosaurus, it is referred to as Anatosaurus by Saurian due to being notably different from the other Edmontosaurus species E. regalis, as well as the 2 million-year gap between their known temporal ranges.
- Mama Bear: Both parents are very protective of their young.
- Recurring Traveller: Will be something of this in the game, owing to them only appearing during parts of the in-game year outside of their breeding season.
- Social Ornithopod: They always travel in herds.
- Tail Slap: As expected from an animal with a thickly muscled tail half its total body length, its main method of defense against predators is lashing them with its tail.
- True Companions: A major theme with Anatosaurus is that they must form a tightly knit herd to keep themselves and each other safe.
Denversaurus schlessmani
Length: 6 meters
Mass: 3 tonnes
Current status: Adults are in-game
A smaller and more social relative of Ankylosaurus that lacks the club tail of its more famous relative, but has several rows of sharp spikes to make up for it. Lost the stretch goal playable vote to Ankylosaurus along with Anatosaurus.- Amazing Technicolor Wildlife: It's dark purple and it's got some fetching stripes on its back.
- Battle Couple: They form strong bonds between mates that help defend each other.
- Hair-Trigger Temper: Even moreso than Ankylosaurus. Justified in that it has to be more aggressive thanks to being smaller and having less powerful weaponry when compared with Ankylosaurus.
- Mama Bear: Or Papa Wolf if they're male, but either way Denversaurus are attentive and protective parents.
- Noisy Nature: Becomes very noisy during the breeding season, though it is quiet otherwise.
- Tail Slap: A useful skill when your tail has sharp spines running along it is hitting enemies with it.
- Tough Armored Dinosaur: A spiked ankylosaur even more territorial than Ankylosaurus, despite being smaller and lacking a tail club.
Thescelosaurus neglectus
Length: 3 meters
Mass: 90 kg
Current status: Adults are in-game
A medium-sized ornithischian that hangs around waterways and feeds on plants such as horsetails.- Amazing Technicolor Wildlife: Has a bright blue dewlap and an orange tail with black and white stripes.
- Killer Rabbit: Despite being small and having no apparent weapons, they are surprisingly aggressive, and when threatened, are more than capable of attacking animals twice their size.
- Red Shirt: Not to the same extent as other prey, but due to its relatively small size and lack of weapons, the adults are easy prey for Tyrannosaurus and adult Dakotaraptor.
- Take Cover!: Being relatively slow and lacking obvious weaponry, hiding among dense foliage is its main anti-predator defense.
Non-avian Theropods
Acheroraptor temertyorum
Length: 2 meters
Mass: 18 kg
Current status: Adults are in-game
A small dromaeosaur discovered in 2013 that mostly targets small prey.- Battle Cry: Its screech is one of the most common vocalizations in-game, especially during the younger stages of Dakotaraptor gameplay.
- Cat Up a Tree: Acheroraptor is slated to be able to climb, but due to its smaller wings and greater mass it is unlikely to be as adept at getting down from trees as young Dakotaraptor, potentially leading to situations like this.
- Demoted to Extra: It was originally a planned playable until the discovery of Dakotaraptor was announced in 2015, at which point it was replaced by its larger relative.
- Eats Babies: Baby dinosaurs are easy prey for it.
- Feathered Fiend: When you're a youngster this dromaeosaur is one of the more dangerous enemies in the game.
- Killer Rabbit: A smaller relative of Dakotaraptor that is a legitimate threat while you're a youngster.
- Raptor Attack: Averted for the same reason as Dakotaraptor—it's properly feathered.
- Starter Villain: Along with Quetzalcoatlus, Borealosuchus, Brachychampsa, Pectinodon, and Palaeosaniwa, it is one of the biggest threats in the hatchling stage of the game.
- Vile Vulture: Its design appears to take inspiration from the bone-eating lammergeier and it's a potential threat to you in the earlier stages of the game.
Ornithomimid
Adult male
Length: 5 meters
Mass: 350 kg
Current status: Adult males are in-game
An "ostrich dinosaur" that, when on its own, mostly relies on speed to escape from predators. In a flock, however, it can easily turn on its smaller enemies. Lost the stretch goal playable vote to Anzu.- Feathered Fiend: In a flock, though on its own it's much less formidable.
- No Name Given: It is currently unknown which genus it belongs to, hence being referred to as "the Hell Creek ornithomimid" by the team, or just "ornithomimid" in the in-game encyclopedia. The dev team at one time gave it the tongue-in-cheek nickname "Deinornithomimus", meaning "Terrible Bird Mimic" or "Moa Mimic" depending on who you ask.
- Super-Speed: One of its two main defenses is to simply run away at high speed.
- Zerg Rush: Its other main defense is to mob predators.
Pectinodon bakkeri
Length: 3 meters
Mass: 35 kg
Current status: Adults are in-game
A troodontid that inhabits the more forested regions inland.- Eats Babies: Baby dinosaurs are optimal prey for it.
- Feathered Fiend: When you're a youngster. Much less so when you're an adult.
- Nocturnal Mooks: Its speed and largely nocturnal nature lend itself to being this to baby dinosaurs.
- Raptor Attack: Subverted in that it's not a dromaeosaur. Even if it was, it's still properly feathered and behaves much more like an actual animal.
- Starter Villain: Along with Acheroraptor, Quetzalcoatlus, Borealosuchus, Brachychampsa, and Palaeosaniwa, it is one of the biggest threats in the hatchling stage of the game.
- Vegetarian Carnivore: It most likely ate plants as well as meat.
Avian Theropods (Birds)
Avisaurus archibaldi
Height: 0.5 meters
Wingspan: 1.5 meters
Mass: N/A
Current status: Planned
A relatively large enantiornithine roughly similar to birds of prey.- Giant Flyer: It's not an ornithurine, the family to which all modern birds belong, though it does inhabit a similar niche. The fact that it has teeth and clawed wings does make up for this discrepancy. It's also easily the size of an eagle, making it very very big by enantiornithine standards.
- Toothy Bird: Played straight. Like most Mesozoic birds, avisaurids are speculated to have had teeth (no skulls of late Cretaceous species remains, but there are Brazilian contemporary fossils that show at least some other enantiornitheans had teeth).
Brodavis baileyi
Height: 0.2 meters
Wingspan: 0.25 meters
Mass: N/A
Current status: Planned
An amphibious hesperornithine bird that dwells in freshwater habitats.- Flying Flightless Bird: It's a member of the Hesperornithes, which are Cretaceous seabirds well-known for most members being secondarily flightless. Despite this, Brodavis is a primitive member of the group and thus retains some volant abilities.
- Jack of All Trades: Unlike its more well-known derived relatives, Brodavis is capable of flight and a competent walker in addition to being able to swim and dive.
- Toothy Bird: Played straight. Like most Mesozoic birds, hesperornithines had teeth; in fact, they and ichthyornithines are the two most famous historic examples of toothed birds in paleontology.
"DePalma's ornithuran"
Height: 0.25 meters
Wingspan: 0.5 meters
Mass: 0.5 kg
Current status: In-game
A small undescribed ornithurine bird that inhabits areas around the shorelines and riverbanks of Hell Creek- Butt-Monkey: One of the smallest animals in-game, it's potential prey even during the hatchling stage.
- Fragile Speedster: Its main defense from predators is its ability to take flight.
- No Name Given: Being previously referred as either "Ornithurine B" or "Bone Butte Bird", "DePalma's Ornithuran" hasn't been either named or formally described as of now.
- Red Shirt: Serves as little more than a prey item during the hatchling and juvenile states, and a bite sized morsel during the subadult and adult stages.
Pterosaurs
Quetzalcoatlus lawsoni
Height: 2.5 meters
Wingspan: 5.5 meters
Mass: 20 kg
Current status: In-game as fly-over A.I.
A large, ground-hunting stork-like pterosaur.- Buzzing the Deck: It does this sometimes in-game, occasionally with the added screeching call that has the effect of startling unwary players.
- Darker and Edgier: Its updated design compared to the original. Word of God even stated that its newer design was inspired by the Grim Reaper.
- Eats Babies: It is perfectly willing to eat baby dinosaurs.
- Giant Flyer: Smaller than its aircraft-sized cousin Quetzalcoatlus northropi, but still big enough to be formidable.
- The Grim Reaper: Its final design, with black wings, a body resembling a cloak, a white, skull-like face and a long, scythe-like beak, draws influence from the classical depiction of Death.
- Lean and Mean: It's tall, slender and terrifying.
- Prehistoric Monster: Downplayed. It still looks and behaves the part of a normal animal, but certainly has a more deliberately menacing appearance and aura than most of the other creatures in the game.
- Starter Villain: Along with Acheroraptor, Borealosuchus, Brachychampsa, Palaeosaniwa, and Pectinodon, it is one of the biggest threats in the hatchling stage of the game.
Crocodylomorphs
Borealosuchus sternbergii
Length: 3-4 meters
Mass: 180 kg
Current status: In-game
A mid-sized crocodylomorph that inhabited North America from the Cretaceous to the Eocene.- Eats Babies: One of the predators you encounter as a hatchling.
- Never Smile at a Crocodile: Slightly downplayed given that it's not a "true" crocodilian per recent phylogenetic studies, but regardless is a recurring enemy for small to mid-sized dinosaurs.
- Starter Villain: Along with Acheroraptor, Quetzalcoatlus, Brachychampsa, Pectinodon, and Palaeosaniwa, it is one of the biggest threats in the hatchling stage of the game. Even as an adult (at least for the smaller dinosaurs), it still remains a threat until the late game. Not so much when you are a grown giant dinosaur (e.g. Triceratops, Tyrannosaurs, or Ankylosaurus).
Brachychampsa montana
Length: 2-3 meters
Mass: 75 kg
Current status: In-game
A mid-sized alligatoroid that lived from the Cretaceous to the Paleogene.- Eats Babies: Occasionally preys on baby dinosaurs.
- Never Smile at a Crocodile: A prehistoric alligatoroid that is one of the predators you encounter as a hatchling.
- Starter Villain: Along with Acheroraptor, Quetzalcoatlus, Borealosuchus, Pectinodon, and Palaeosaniwa, it is one of the biggest threats in the hatchling stage of the game.
Thoracosaurus neocesariensis
Length: 8 meters
Mass: 1 tonne
Current status: Model is being animated
A massive coastal-dwelling crocodylomorph that resembles modern gharials.- Bigger Is Better: Seems to be the mindset of many players who were aware of Thoracosaurus and eagerly anticipated its size reveal, which had been kept secret for years.
- Never Smile at a Crocodile: Downplayed due to not being a "true" crocodilian. Regardless, at 8 meters (26 feet) long - bigger than the largest recorded saltwater crocs - they're the largest known crocodylomorphs in Hell Creek, likely capable of killing mid-sized dinosaurs with relative ease despite their narrow jaws.
- Sea Monster: Whilst not a true supercroc, the thing is still quite large and dangerous to most creatures in or near coastal habitats, being the second largest aquatic animal in the game after Mosasaurus.
Choristoderes
Champsosaurus sp.
Length: 3.5 meters
Mass: 150 kg
Current status: In-game
An aquatic reptile resembling a gharial, but not closely related to any living animal.- Artistic Licence Paleontology: Is depicted as essentially a crocodile-snouted iguana, a look based on the much smaller and lizard-like choristodere Larassuchus and unlikely for the fully aquatic choristoderes.
- Crippling Overspecialization: They are so well-adapted to aquatic life that males lose the ability to walk altogether and females only barely retain the ability in order to haul themselves ashore to lay eggs, making them quite vulnerable on land. The ones in-game will outright die if they get too far out of water.
- Never Smile at a Crocodile: Not a crocodile per se, but greatly resembles one. Also subverted in that they aren't all that threatening to most playable dinosaurs.
Testudines (Turtles)
Axestemys infernalis
Redesigned coloration
Length: 1.5 meters
Mass: N/A
Current status: Planned
A large, mostly aquatic softshell turtle.- Sturdy and Steady Turtles: Subverted. Softshell turtles are opportunistic predators and surprisingly aggressive, capable of quick strikes with their powerful jaws. They're also known for their speed; even the larger ones are remarkably fast on land.
Basilemys sinuosa
Length: 1.5 meters
Mass: 100 kg
Current status: In-game
A large terrestrial turtle that is often found foraging for plants near water sources.- Sturdy and Steady Turtles: The best in-game embodiment of this trope; it walks slowly and retracts its head into its shell when threatened, which is usually an effective defensive measure except against adult Tyrannosaurus.
Toxochelys sp.
Hatchlings
Length: N/A
Mass: N/A
Current status: Hatchlings at least are planned
An ocean-going turtle that independently converged on the body plan of modern sea turtles.- A Million Is a Statistic: Hopefully players can take solace in this when they gorge themselves on large groups of baby Toxochelys alongside other opportunistic AI carnivores.
- Red Shirt: They pretty much exist to provide a periodic bounty for opportunistic players.
- There Are No Adults: According to the devs, only baby Toxochelys are currently planned to appear in-game.
Squamates (Lizards)
Chamops segnis
Length: 0.5 meters
Mass: 2 kg
Current status: In-game
A lizard native to Hell Creek, part of an entirely extinct group.- Amazing Technicolor Wildlife: Its head is bright red, while the rest of the body is black.
- Butt-Monkey: It's not only food for the players, but also for the ambient Acheroraptor, meaning they are always at the bottom of the food chain.
- Fragile Speedster: While it will go down in one bite, actually hitting it is difficult, as it moves very fast.
- Red Shirt: Its sole purpose is to be food for baby Tyrannosaurus and Dakotaraptor.
Mosasaurus hoffmannii
Shown with (above) and without (below) lighting
Length: 17 meters
Mass: N/A
Current status: In-game
Enormous marine reptiles related to snakes and monitor lizards that inhabit the Western Interior Seaway.- Alas, Poor Villain: For a given value of "villain". Even though it's a massive threat to your dinosaur character regardless of species, it's a little bit sad to see such a mighty creature beached and dead on the shore. Unless you're a starving carnivore, of course...
- Always a Bigger Fish: At 17 meters long, even a Tyrannosaurus wouldn't last long against them if swimming in their domain.
- Amazing Technicolor Wildlife: Averted. The unused concepts come in bright green◊, yellow◊, and striped brown-red◊, but the colour of the the final model is greyish blue with some faded stripes.
- Border Patrol: Their attacks will prevent you from swimming too far into the inland sea, and despite being independent creatures are unbeatable and impossible to kill, which is a heavy case of realism as even something as mighty as a Tyrannosaurus would be no match for a massive underwater apex predator in its own territory. However, it is possible to actually escape an attack and return to shore, as well as to discover the carcass of one washed ashore on the beach.
- Expy: The role it plays is intentionally similar to Snacker the Shark and the Lurker Shark, according to Word of God. Behavior-wise, though, it's most similar to the Ghost Leviathan from Subnautica, as it only spawns when you get to the edge of the map and goes away if you get back inside fast enough.
- Malicious Monitor Lizard: Mosasaurus is essentially a gigantic Komodo dragon with fins, helped by the fact that mosasaurs are related to monitor lizards. Although it is less malicious and more hungry.
- Misplaced Wildlife: Very, very downplayed, as initially Mosasaurus wasn't known from Hell Creek, but it is known from the nearby Fox Hill Formation which also occurred at the late Maastrichtian of South Dakota. However, large mosasaur fossils have recently been found in Hell Creek rocks, so its inclusion in the game is further justified (whether these are Mosasaurus fossils is still not clear).
- More Teeth than the Osmond Family: Along with the regular set, it has an extra set on its palate.
- Sea Monster: A massive, predatory lizard that lives in the Western Interior Seaway. In-game, their role is to prevent you from swimming too far out.
Palaeosaniwa sp.
Length: 2 meters
Mass: 25 kg
Current status: In-game
A large, carnivorous and venomous Komodo dragon-like lizard.- Eats Babies: Preys on baby dinosaurs.
- Malicious Monitor Lizard: It is a large, predatory lizard related to monitors. The "malicious" part, however, is downplayed in that it's just trying to survive.
- Mix-and-Match Critters: The size, appearance, and general niche of a Komodo dragon, but the scales of a Gila monster.
- Poisonous Person: Venomous in-game, owing to its closest relatives being Gila monsters and beaded lizards.
- Reptiles Are Abhorrent: A large venomous predatory lizard. Downplayed in that it's simply a hungry predator rather than a true villain, though that probably won't make much difference to you as a hatchling dinosaur.
- Starter Villain: Along with Acheroraptor, Quetzalcoatlus, Borealosuchus, Brachychampsa, and Pectinodon, it is one of the biggest threats in the hatchling and even juvenile stages of the game.
- Who's Laughing Now?: A terror for the player when they are still a hatchling and even as a juvenile, but the minute you hit subadult (at least as Dakotaraptor) it starts running away from you.
- Your Days Are Numbered: If you get bitten at a certain size (typically as a juvenile or even subadult Dakotaraptor) you enter an unstoppable death spiral that can last up to several minutes.
Mammals
Didelphodon vorax
Length: 1 meter
Mass: 5 kg
Current status: In-game
A large (for the Mesozoic) carnivorous mammal with a proportionately powerful bite force.- Artistic Licence Paleontology: Portrayed as terrestrial when i reality it was semi-aquatic.
- Cute, but Cacophonic: Its calls are based on those of Tasmanian devils, which are terrifying.
- Mix-and-Match Critter: Has a Tasmanian devil-like skull on the body of an otter.
- Red Shirt: Its sole purpose is to be food for baby Tyrannosaurus and Dakotaraptor and a bite-sized morsel for older Dakotaraptor and other mid-sized carnivores. Didelphodon gets hit especially hard because it is very slow, making it extremely easy for the fast running predators of Hell Creek to tear it apart.
- Take Cover!: Hiding among dense undergrowth will be its main anti-predation strategy.
Meniscoessus robustus
Length: N/A
Mass: N/A
Current status: Planned
A nocturnal, herbivorous member of an extinct group of ancient mammals called multituberculates that is mostly found in forested areas.- Red Shirt: It just exists to add variety to the prey base of baby Tyrannosaurus and Dakotaraptor.
Amphibians
Habrosaurus dilatus
Length: 1.5 meters
Mass: N/A
Current status: Planned
A giant aquatic siren salamander.- Amphibian at Large: One of the largest lissamphibians of all time, measuring over 1.5 meters (5 feet) in length.
Fish
Lepisosteus occidentalis
Length: 0.6 meters
Mass: 2 kg
Current status: In-game
A freshwater fish closely related to modern longnose gar.- Fishing Minigame: More than just an ambient AI, its inclusion marked the first time players had an opportunity to try their hand at fishing.
- Expecting Someone Taller: Due to modern gars' reputation for being considerably large fish in the 2-3 meter (6-9 feet) range, the fact that L. occidentalis is barely a half a meter long (thus one of the smallest creatures in the game) was quite the surprise to a lot of players.
- Red Shirt: They mostly exist to be consumed by players willing enough to try catching them.
Lonchidion selachos
Length: 1 meter
Mass: N/A
Current status: Planned
A small freshwater shark adapted to eat mollusks and other hard-shelled prey.- Fishing Minigame: They'll be a "fish-able" creature.
- Red Shirt: Too small to have any meaningful predatory interactions, they mostly exist to be consumed by players willing enough to try catching them.
- The Spiny: The decently large spines in front of each dorsal fin might make them a bit more challenging to catch and eat without injuring yourself.
- Threatening Shark: Averted; at barely a meter (3 feet) long, it's one of the smaller creatures in the game and specializes in hard-shelled mollusks rather than flesh-tearing.
Invertebrates
Casterolimulus kletti
Length: N/A
Mass: N/A
Current status: Planned
A prehistoric horseshoe crab, and the only named invertebrate in the game.- Anatomy Anomaly: Prior to the new T. rex design, Casterolimulus was the only animal to be modeled with an anus.
- Misplaced Wildlife: Very, very downplayed, as Casterolimulus isn't known from Hell Creek, but it is known from the nearby Fox Hill Formation which also occurred at the late Maastrichtian of South Dakota.
- Storming the Beaches: To make love (spawning), not war.
