- The early years
of the Kyran Islands seem seem like a fairly nice place to live with no large predators, fruit-bearing trees, and big peaceful birds known as chubbirds. However, once the mother chubbirds leave the nests to go foraging, the chicks are set upon by◊ basketball sized hermit crabs that devour any of them that aren't able to kick them away. Even when they grow larger, a flaw in their growth rate means they still aren't able to get up and escape when many times bigger than the crustaceans so they can only just sit there and do nothing◊ while the crabs pick pieces out of them. About 85% of all chubbird chicks are killed as a result and even many of the ones who do survive are left with permanent scars and missing appendages. - The Lanks◊ are a species of flightless stork-like birds that are one of the apex predators of the Kyran Islands. They use their massive bills to impale their prey and are said to possess a call that sounds like a damaged tornado siren. What's worse is the fact they stand over twenty feet tall, this combined with their strangely lanky neck and legs make them more unnerving than the comparatively more robust Bonebeaks.
- The fate of male chimera ants. Newly dispersed males will carry off seedlings, dig burrows, and call for a mate. If he's lucky, he'll find a winged queen, mate with her, and build a colony together. However, while queens can live for as long as fifty years, males live only several years. So once her mate dies, what does a chimera ant queen do? Produce a batch of winged workers that mimic queens to lure in a new male calling for a mate. They then capture him, tear off his mandibles and wings so he can't escape or fight back, and then haul him back to the nest to essentially be a sex slave of the queen, being force-fed by workers for the rest of his life, as he no longer has jaws to eat with. The worst part? The queen accepts only one male at a time. In the event that the winged workers bring multiple males back home, the first-comer becomes her new groom... and the rest are her dinner.
- The Thermocene/Pangeacene mass extinction. Extreme volcanism completely buries one continent, blots out the sun for months at a time, and, most catastrophically, creates a greenhouse effect that makes the one Earth currently faces look like a warm spring day. Photosynthesis and thus carbon dioxide absorption has ceased to occur except for one thin strip of forest on the new supercontinent's southern shore and a few pockets of polar sea that still hold oxygen. The rest of the oceans are nothing but a scalding anoxic soup of bacteria. Serina's equator is too hot to support any life while its temperate and polar regions are completely covered in ice. The lack of atmospheric oxygen even causes the ozone layer to thin, putting what life survives at high risk of mutation from cosmic radiation. The extreme Disaster Dominoes makes one worry about how our own world could end up if we're too slow to act...
- The greater grappler, which has clawed and spike-lined tentacles hiding a huge hooked beak, stands nine feet tall, and weighs half a ton. The scene introducing the species is written in a tone more fitting for a monster attack in a horror novel, uncharacteristically for the site. It also has a smaller, faster relative called the grapplepard◊. It still stands almost as tall as a man, still has fanged tentacles, and, as its name implies, holds the niche of a big cat as a stalking-and-ambush predator. And it can climb trees as long as they aren't too straight. And all grapplers are fairly intelligent.
- Some of the more advanced changeling birds are disturbing in a more Unintentional Uncanny Valley way for anyone who knows what a bird should look like. Many of them look more like insects than avians, and there's even a species that has a parasitic larval stage similar to that of a botfly.
- The carnivorous wheeljaws◊ look rather disturbing, having a mouth resembling a cross between a bird's beak and a buzzsaw.
- There's something rather unsettling about the description of early carnivorous wheeljaws using their resemblance to their herbivorous cousins to infiltrate their herds and take them out from the inside. From the perspective of the herbivores, it's the equivalent of being hunted by a horror movie monster that Was Once a Man and Looks Just Like Everyone Else.
- Later on, we get to see what they look like after having more time to evolve and they're a real piece of work. Their jaws have developed a wicked looking hook and even nastier serrations and it's mentioned that they have a tendency to eat their prey alive. Not to mention that they look an awful lot like a bulldog of sorts...but not quite.
- The billion-stingers are a species of ant similar to Earth's army ants, except their colonies are far bigger, and travel in mobile nests of their own bodies. They are fierce and deadly enough to attack deer-sized circuagodonts and strip them to the bone in a matter of minutes.
- The Repandor, seen in the page image, looks like some kind of canine or thylacine crossed with a banana at first glance... until it opens its mouth, revealing a set of extending jaws with More Teeth than the Osmond Family. The Brushbounder also has a similarly nasty set of fangs.
- While a placid omnivore, the thorngrazer◊ is rather startling to look at, especially with all the spines growing out of its face. Its ice age descendent, the sextacorn thorngrazer, takes it even further by having six large horns◊ coming out of its face.
- The gravediggers are carnivorous bumblebadgers that are among the top predators of the Ultimocene. What makes them more frightening than, say, a bear is they are highly intelligent, and hunt their prey by digging pitfall traps lined with spears. Eventually, they become true sapients and wage war on their prey, the antlears, but when the climate change gets dire and the two species are forced to work together, the Gravediggers become the antlears' hired muscle... paid for their labor ''in the form of getting to eat the antlears' dead''.
- The leak of the finale "arc" (now deleted from the Speculative Evolution forum) of the Middle and Late Ultimocene may have been rushed, but had rather a lot of this for its short length. To think the world started with canaries, guppies, and sunflowers...
- The Nightmare Fuel aspect is eventually subverted, as we learn more and more about the Gravediggers' culture, and they become truly sympathetic as a species.
- Cutthroats are an unpublished predatory molodont species whose jaws are massive serrated blades based on tiger beetles. There was even concept art of a saber-toothed molodont whose upper jaw crosses asymmetrically over the lower as its blade-like teeth are too big to fit in its mouth.◊ This species has since made its official debut as the saber-toothed circuagodog, and it's still quite uncanny.
- There's also the tentatively-named Unnamed Giant Molodont Predator, a large apex predatory form resembling some sort of semi-mammalian ''Carnotaurus''. Most disturbing is its distinctive red neck markings that give the impression of ''having had its throat slit open''. It has now made its canon debut as the Cutthroat Subjugator, a massive tyrannosaur-like predator with jaws designed to crush the throats of cygnosaurs.
- One of the very last species in the late Ultimocene are the shoggoths. Immense ant colonies descended from aquatic symbiotes of sea bamboo, their colonies form colossal, writhing masses with grabbing tentacles formed of their own bodies, and it's mentioned that they even incorporate the fur and feathers of their prey as insulation and use their bones as an internal skeleton with the ants themselves acting as the muscles, forming an enormous, shambling mass of billions of living insects and parts of animal carcasses... For once, it's a relief that Sheather didn't illustrate a creature, or maybe it isn't.
- Oh, don't worry. Fans have you covered. Sweet dreams, everyone.
- The sea shoggoth made its official debut on October 3, 2021, and isn't helping anyone's thalassophobia. Its illustration depicts an undulating black form sitting low in the water, tentacles reaching out to ensnare metamorph birdfish. Oh, and its scientific name is Informonstrum ingurgitos, meaning "formless devouring monster".
- Oh, don't worry. Fans
- The grisly carnackle is a trunked softbill bird descended from the neckbeard. Its face is covered with knobbly red featherless skin, its trunk is covered with defensive spines, and even its head and neck are adorned with Spikes of Villainy, which, coupled by its black, cloak-like plumage, looks every bit like a satanic eldritch turkey.
- The woodcrafters are downright frightening in their extreme Animal Jingoism and misplaced ideology, seeking to free all their kind from predators. Which they achieve by hunting said predators with spears, brutally torturing them to death while reveling in their slow, painful demise, and taking their skins and heads as trophies. Keep in mind that the woodcrafter is a herbivorous species with no need to kill to survive yet does so for sport, and that its target is itself a sapient creature...
- The part where the woodcrafters discover that the gravediggers they were hunting were sophisticated creatures making complex art— and they were the monsters all along.
- The Skewer from "Life of the Cactaiga" (not to be confused with the Skewer from Expedition) is a basal changeling with the Squickiest methods of feeding in all of Serina: it impales its prey on its movable, needle-like upper beak, then inserts a long, spiky tongue into the wound that it uses to scrape and suck out the internal organs and blood.When it finishes feeding, only an empty husk of skin and bones will remain with all of the flesh removed through a single small entry wound.
- While nops aren't horrifying in and of themselves, looking like oversized canary chicks mixed with a porpoise, the way they came to be is. The pastoralist daydreamers bred their porplet ancestors for docility so much that all a nop can do is eat, poop, and sleep, and are completely helpless without their predator keeping watch over them. The ability to feel pain was bred almost entirely out of them, so a nop can get Eaten Alive and will just continue grazing until their bodies are too broken to continue, though fortunately their pastoralist sheperds will Mercy Kill them first before eating.
- The warmongers. Dark-skinned, scar-ridden, giant daydreamers that are the top predators of the Middle Ultimocene seas. What makes them truly frightening is that they are sapient beings who are perfectly happy to kill and even eat other sapients: a behavior borne from self-proclaimed superiority that gives them the right to exterminate all "lesser" beings. Because what's more terrifying than a razor-beaked predatory orca-bird? A razor-beaked predatory orca-bird that is, for all intents and purposes, a cannibalistic aquatic Nazi. Upon finding out that the gravediggers are sapient, the leadership decides that this threat to their superiority cannot be tolerated and decide to try genociding them too, overturning their boats and eating them alive. This makes it clear that they're the Shadow Archetype of the woodcrafters. Unlike the woodcrafters who made peace with their former predators after discovering sapience in the gravediggers, the first thing the Warmongers thought after doing the same thing was to mercilessly kill them.
- During the war with the warmongers, they fishers and pastoralists use gravedigger-made spears laced with the paralytic poison of the fireslime lumpus in the second battle. Due to daydreamer size and physiology, not only is the poison deadly to the warmongers, they can take up to half an hour to drown while paralyzed if they're not eaten alive by predators attracted by the blood of the battle, fully aware the whole time. The warmongers themselves take it as chastisement from the Creator for their actions.
- The warmonger matriarch is exiled from the group, blinded by the vengeful mate of one of her soldiers, and ultimately Eaten Alive by a sea shoggoth, fully aware the whole time.
- In order to try staving off the encroachment of the glaciers, the sea stewards decide to start mining coal in Serinarcta, now mostly an icy wasteland, in order to create a fire big enough to destroy the ice bridge threatening to disrupt the currents they need to stay alive. The dangers include the savage gravediggers, which unnerve the thalassic gravediggers with their similar appearance and their ability to plot and probe for weaknesses in the camp walls despite their lack of higher intelligence, and the thorngrazers who the thalassics refer to as "ever-eaters" for their ability to eat just about anything in their path and only kept away by their fear of flame.
- It's mentioned that sometimes the thorngrazers will manage to push their way past the walls, only to fall into the pits surrounding the camps and be gravely injured, the gravediggers huddling in fear inside their underground sleeping places as the pits turn into a feeding frenzy for Serinarcta's predators upon nightfall, who eat the thorngrazers alive.
- Whitecrown's flock accidently manages to spark a coal seam fire while hunting, and this causes a fire so great that it consumes them, Brighteye, the woolly wumpos, and everything else on Serinarcta unable to escape. To boot his illustration is on an eerie white with red glowing.
- The watcher gives Seeker the greenskeeper a view of the future if he and the other sea stewards choose not to take their offer to be planted on a world where they never learned of Brighteye's existence, and die with the Late Ocean Age. In it he sees that the thalassic gravediggers have devolved into nonsapience and have chosen to devour the corpses of the daydreamers and greenskeepers who were killed by the subsequent ocean acidification.
- "Are you my mother?" is told from the point of view of an equinox foal about to be eaten by a kelpie who has mimicked the call of an equinox mother. He feels that something is off when he realizes "his mother" doesn't smell or look like he remembers her… but because he keeps hearing the call he is used to, he doesn't try to escape or signal for help until it is too late. It is disturbingly similar to the techniques used by human child predators.
- The imperious river dragon is an eelsnake that has evolved to become so large that only the absolute largest of the cygnosaurs can escape predation by them, with the largest sea dragons being longer than a school bus and twice as heavy as an elephant, while strong enough to knock over a ten-ton herbivore with a single strike of its tail.
- The final mass extinction is pretty frightening in both its existential dread and inevitably. While not as intense or dramatic as the Thermocene extinction, at least that catastrophe was over pretty quickly (geologically speaking) and life quickly recovered afterwards. The Ultimocene extinction is caused by the planet's core cooling down, meaning that it can't be prevented, halted or reversed and once it starts, the world and all life on it are silently condemned to a grim drawn-out death. Once the Mid-Ultimocene hits, almost every entry is about life on the brink, starting with how previous lush ecosystems have collapsed, and often ending with the threat of extinction looming over whatever survivors we see. After reading a few entries, it sinks in just how omnipresent and inevitable the extinction of life on Serina is.
