Hahaha okay I concede the point on leopard milk. For now
Update time, I've added a "bestiary" section at the beginning with descriptions of some of the less obvious critters, also fixed the place-names and changed some of the creature names around, and added the Heartlands below:
Colovian:
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Fyn: A small, domesticated alphyn, serving as hunting dogs and companion animals for the Colovian nobility.
Alphyn: Avian predator (top left in the below concept), primarily nests in the northwestern cliffs of the Highlands but can travel as far east as the Massiquerran Forests in search of prey and can easily fly carrying a full-grown deer.
Tantha: A timid creature living in the Gold Coast and lower Highlands where it makes its nests underground. Primarily eats small insects, fruit, and leaves.
Cardoon: Northern relative of the tantha, it has adapted to a relatively more dangerous environment by evolving a spiny hide and sharp claws with which to ward off would-be predators.
Nibenese:
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Virmilin: Domesticated farm-beast of Nibenay, it is well-adapted for traversing swamps and dense jungle and feeds on the rust-ants that build their nests in the rich red soil of the riverbanks. Most plantations will devote a corner, far from any inhabited structure, to these ant colonies in order to feed their livestock. Letter E in the below concept.
Neofelis: Large jungle cat of Nibenay, though of no relation to the tigers. Prized as pets by the Nibenese nobility, though they can never be entirely tamed.
Koupi (plural "koupii"): Giant otters of Nibenay, colloquially referred to as "water wolves" by the locals for their tendency to prey on farmers' newt herds (and rarely, the farmers themselves).
Coutal: Pack-beast originally domesticated by the Kothringi, a practice which was taken over by the Nibenese peoples after the Knahaten Flu all but wiped out Cyrodiil's population of the tribe.
Makon: Eastern relative of the tantha, adapted for life in the rivers. A naturally powerful swimmer, when it is trapped or injured by predators like the koupii or river-drake, it can deliver a powerful toxin from its claws or barbed whiskers.
Domesticated (Colovian Settlements)
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Cow/Bull
Horse
Goat
Donkey
Fyn
Gold Coast/Gilded Foothills
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Dry, arid scrublands, primarily consists of small omnivores and aquatic life with sparse packs of mid-size predators. Herds of wild horses can be found around sources of fresh water, which draws the attention of larger wolf packs. The resource-parched wastes between major landmarks are dominated by the goblin tribes, whose squabbles for territory only draw Imperial ire when they come too close to a population center.
Tantha
Rat
Wolf
Seagull
Horse
Lamia
Passive fish
Moon Crab
Slaughterfish
Dreugh
Land Dreugh
Goblin
Durzog
Colovian Highlands/Barrowlands/Kvetchi Pass
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Vast savannah, with herds of mid-size/large herbavores ranging for grazelands and fresh water, stalked by the apex predators that rely on them for sustenance. Further north, the landscape transitions to rocky cliffs more suited to sure-footed and hardy goats and donkeys than herds of wild horses. Minotaur clans are primarily clustered around the ruins of Sancre Tor, but scavenging and hunting parties can be found far to the south and west, and are best avoided by adventurers lest their remains be added to the clan-treasures.
Horse
Deer
Bull/Cow
Goat
Wolf
Mountain lion
Alphyn
Minotaur
West Weald
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This region shows the most Imperial influence on its landscape, leaving few untamed spaces for monsters to flourish. Packs of feral hawk-dogs, and disease-carrying rats and petty trolls are the worst nuisances on the surface, while the sewers have been all but overrun by one or two of the more ambitious goblin tribes.
Deer
Fyn
Rat
Petty Troll
Goblin
Durzog
Wolf
Passive Birds
Massiquerran Forests
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Beneath the shade of the great oaks, a vibrancy of life and biodiversity flourishes. Deer and small game abound, as well as larger predators, and while the fauna is rarely desperate enough to come after humans, the ever-vigilant presence of the forest's spriggans still makes hunting a risky venture. The southern minotaur clans are less hostile than their northern cousins, and will even engage in trade with clan-friends, though their trust is hard-earned.
Deer
Rat
Boar
Squirrel
Petty Troll
Wolf
Fyn
Alphyn
Bear
Spriggan
Minotaur
Passive Birds
Domesticated (Nibenese settlements)
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Newt
Vermilin
Carnelian Snail
Ancestor Moth
Neofelis (pet)
Donkey
Ruma Floodlands
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The marshes of Rumare are said to be the meeting point of Colovia and Nibenay, but the environment is decidedly Nibenese. Certain bold members of the Colovian fauna can still be found picking their way through the region's driest areas, as well as certain Nibenese predators willing to leave the shores, but the region's most successful wildlife are those adapted for both land and water.
Troll
Petty Troll
Deer
Vermilin
Bull/Cow
Boar
Bullfrog
Wolf
Newt
Water Wolf
Passive Birds
Passive Fish
Heartlands
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A discussion of Heartland ecology must begin with that old warning: "Here there be dragons." The serpentine river-drakes rule the Rumare even as the Emperor rules from his Isles, while Akaviri red dragons patrol the skies above. The wildlife here is adapted to surive in these conditions, either small enough and well-camoflagued to escape notice, or else nocturnal so as to go about their business unchallenged.
River Drake
Red Dragon
Bullfrog
Newt
Deer
Boar
Passive Birds
Passive Fish
Ora Demergatur
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The flood of the eastern shore did more than wipe out the Imperial villages there, it also devastated the natural ecosystem there in ways that it may never fully recover from. The odd scavenger can be seen picking through the ruins, and stick-legged birds hunt for what few fish can survive in the murky waters, but little else can survive here.
Troll
Petty Troll
Rat
Mud Crab
Slaughterfish
Passive birds
Serican Woods/Valley of Altars
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The dense jungle is home to more species of bird and moth than one could count in an Altmer's lifetime - however, the rivers are home to Nibenay's true biodiversity. Shy plant and insect eaters dart to and from the water's edge, mindful of the predators who stalk both the treeline and water's edge.
Passive birds
Ancestor moth
Vermilin
Boar
Deer
Newt
Koupi
River-Drake
Moon Crab
Slaughterfish
Neofelis
Spriggan
Will-o-wisp
Troll
Petty Troll
Serican Woods (Interior)
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The usual chatter of bird and petty troll fades away the moment one crosses into the dominion of the tigers. It is known that the dragon-cats cultivate populations of certain prey animals, but a complete listing of the species here is made impossible by the strict prohibition against entering these woods without the express permission of both Emperor and Elder Council.
Tiger
Deer
Cow/Bull
Ancestor Moth