So I found a thing via this guy's excellent blog
Specifically, an eco-system generator which creates names of major flora and fauna and provides landmarks and encounter tables ready to go.
Anyway, here's what I got
Plant: Violet Grass, Mercury Berries
Herbivore: Phase-Oxen, Thunderfolk
Carnivore: Canopy Owl, Manticore-Scorpion
Apex Predator: Curse Phoenix
Scavenger: Circular Larvae, Vile Urchin(s?)
Weird Thing: Umbral Child
ECOSYSTEM: THE PURPLE PLAINS
Phase-Oxen herds shift in and out of the ethreal plane, becoming solid to eat, passing like ghosts over the violet grass during the hottest parts of the day. They must be caught unawares in order to be successfully hunted. The Thunderfolk often leave these herds offerings of crushed berries and sweet grass. When they hunt the oxen it is with the bow, and they always shoot to kill the animal with a single arrow through the breast or neck. Phase oxen rapidly grow a white, electric-blue tinged shaggy coat like muskoxen in Winter, shedding most of it in Summer. Translucent "ghost strands" of their dropped fur are carried on the wind like stringy pollen in Spring.
The Thunderfolk use much from the Phase-Oxen to sustain their way of life. Dung for fuel, the electric-colored furs for mantles, their great horns for instruments (the use of massive signalling horns is the reason for the name Thunderfolk). They follow the herds in a semi-nomadic pattern, digging and reusing dug-outs with simple hide coverings to complete the structure. These coverings can be folded up and carried with the Thunderfolk wherever they go. Despite the simplicity of their material existence it would be a mistake to dismiss the Thunderfolk as primitives, for the Violet Planes stretch across a key trade route and the Thunderfolk commonly interact with merchants from the West. Every band has some sets of swords and mail in case of war, modern saddles for their rangy ponies, and fashionable dresses and ornaments for their women. Among themselves they use "milkstones" (polished white opals) as a kind of limited currency , usually just to make up the difference in various exchanges.
Depending on the band Thunderfolk will sometimes expect "tolls" from travelers or caravans passing through their territory. The kingdoms of the west consider this no more than unlawful banditry and such impertinence to their subjects fit for death.
The Thunderfolk venerate the being they call the Umbral Child, seen listlessly wandering the grasslands alone. To them it is prophet and the will of the gods incarnate. They leave offerings along the Child's path but rarely approach within 100 yards of it. The offerings are always ignored by the steadily walking Child, but for tradition's sake they are always left. Offerings are usually grass dolls, oxhorns, strings of teeth (human, ox, horse), shards of glass, precious stones etc. These offerings are hung from reed poles stuck into the earth along the Child's path, and thus these pathways are marked with hundreds of such poles snaking along the plainlands. Children are often told it is bad luck to run across the path of the poles, but this is just a wives' tale. A more complicated spin on the story is that it is good luck to run through the path if one is behind the Umbral Child, bad luck to run through if ahead of the Umbral Child. Multiple crossings will cancel each other out so removing ill-luck is as easy as running back through the path, but good luck will be canceled out if one recrosses the pathway, etc. In practice since these pathways stretch in serpentines and loops all over the Purple Plains, crossing them is a common occurence.
If you actually have the stones to approach the Umbral Child, it will prophecy at you. The prophecy always comes true but never in the way you'd expect (or usually want). The few Umbral Child prophecies on record (the Thunderfolk use a simplified Dwarven runic system written in berry-ink on strips of oxhide for such records) are poetic gibberish and there are literally dozens of possible exegeses for each. If the Umbral Child prophecies at you and you start demanding explanations, it will likely strike you dead. The Umbral Child will never harm children, pregnant/nursing women or the very old, but never prophecies at them either. Everyone knows that if you are somehow stupid enough to actually get within six armspans (~10 ft) of the Umbral Child, you will fall dead at once (though nobody remembers anyone ever actually trying this). If you shoot an arrow at the Umbral Child, you will explode---the Priests are very specific on this point.
Many people claim to have dreamed of the Umbral Child, or that the Umbral Child came to them in dreams and told them such and such, and so-on. The Priests of the Thunderfolk declare about 90% of these experiences to be fatuous. If you answer a series of questions correctly ("did you see the Umbral Child in a house?" "did the Umbral Child pass over a stream?" etc.) the Priests will conclude your dream was real and send you on a quest to hear the Umbral Child prophecy at you. Most Thunderfolk conflate actually hearing the Umbral Child prophecy with asking for trouble, so if you pass under a saddle and dump a bowl of milk on your head while groveling about how sorry you are, you are permitted to not do the quest. Lots of people just talk about their Umbral Child dreams without ever going to the priests, which is considered slightly blasphemous but permissable.
The Umbral Child is an adolescent figure, about four and a half feet tall with a bald crown. It walks swathed in a moving darkness like a cloud of thick dust, and the planes of its features are only scarcely visible when it moves for the Umbral Child appears to be made out of solid darkness itself. The Umbral Child is never seen at night, only in daylight, and it is visible from a long ways off as a flickering blackness like a fire walking the purple grass. Close-up, the whites of the Child's eyes and its white teeth are perfectly clear amidst the darkness. It's said that the Child will smile at you if you manage to annoy it.
Vile Urchins are not well understood but believed to be created by the Umbral Child for an unknown reason. They are grey-skinned, dirty creatures that look like children about nine or ten years of age (making them a little taller than Halflings). They dress in greasy rags and wrappings, their long unkempt hair always as pitch black as their eyes. They have enormous, gaping mouths with big flat teeth ideal for grinding, their gums pitch black. Vile Urchins are host to a wealth of parasites themselves, flies and gnats always swirling around them, buzzing and stinging. They travel the purple grass in gangs of six to twelve, looking for carrion which they seize with the speed of crows. Vile Urchins will not attack humans unless interfered with. They are usually encountered tailing a band of Thunderfolk on the move, eating any offal, spoiled meat, or other edible remains the band leaves in its wake. The Thunderfolk are always careful to maintain a distance from the Urchins while leaving them alone, and after feeding for a while the Urchins will usually latch onto some other band and move on. It's said that Vile Urchins are the reincarnated spirits of children who died in childbirth, relegated to the sad fate of a lonely and marginal existence. They are believed to prophecy, and sometimes in exchange for a gift of meat or marrow-bones they will spit out a snatch of future happenings. The relevance of what they say is not always obvious; some warn that the Urchins are liars and cannot prophecy at all. Urchins are so hideous and frightening that people who see them closer than at the edge of the horizon will often perform a small ablution ritual just to be safe. On the other hand, if a child becomes lost the Urchins will always find him and return him to his parents. They are both unclean and acknowledged as not evil, and occupy a strange place in Thunderfolk society.
Manticore-Scorpion seems redundant, since Manticores have the tail of a scorpion already. Manticore-Scorpions, or Scorpion-Manticores, also have a huge pair of armor-shelled claws similar to the Emperor Scorpion, and beneath the chest a smaller pair of mole-like digging claws, for they are burrowing creatures. They are wingless; their four-legged body is vaguely leonine, but hairless (like the naked molerat). They have a human face which bears resemblance to an ugly, hairless, wrinkly old man. Like the regular kind of Manticore they can speak, but they are stupid as hell. When burrowing they cover their face with their armored claws and dig away with their lower pair of hands. They usually burrow at a depth of 6-10 feet, and at that depth can sense the presence of heavy animals such as horses and Phase-Oxen overhead. They prefer to burst upwards from the ground and attack with their tail first, which secretes a paralyzing venom (this is a necessary tactic when hunting Phase-Oxen). Manticore-Scorpions often suicidally attack bands of Thunderfolk---again, they are stupid as hell and prone to overestimating their own prowess. Their shell-platings are used for armor, their venom sacs for hunting arrows, their claws for adornment or affixed to the heads of warclubs. A cloak of the pale-pink Manticore-Scorpion hide is often the choice adornment for Thunderfolk patriarchs.
Canopy-Owls are a horrific predator that combine the worst parts of owl, stingray and flying squirrel. They lurk in trees and tall bushes, their "wings" enclosed over their heads showing a dull bark-like outer coloring. In this way they can be mistaken for burrs or wood galls even on close inspection. When the Canopy-Owl "opens" its great smooth wings sweep up dramatically and join together over its owl-like head, two natural hooks joining so that the Owl's "wings" fully encircle its head like a big bell or parachute. The Owl releases its single clawed "leg" and drops out of the tree, making a fast and precision-controlled descent at its prey with a razor-sharp beak. If this first fall doesn't kill the prey, it unhooks and twists its wings and drives itself back into the air with a whirl to repeat the attack. The inner side of the Canopy-Owl's wings and its head are snow white, occasionally spotted. The skin of its wings is smooth while the head is feathered, just like a normal owl's. It is presumed this beast is wholly unnatural and probably the creation of some deservedly forgotten wizard. Their beaks are as big as daggers and wickedly curved; they will hunt any creature unlucky enough to pass under their bough but they seem to prefer humanoid targets and know to strike for face and throat first. The Thunderfolk call these things "deathshriekers."
Circular Larvae (or just Circle-Larvae) are bizarre and aggressive scavengers that congregate on any large corpse left lying on the Violet Grass long enough. They usually appear to be a smooth, pinkish convex lump of flesh lying on the ground like some kind of big wart (they are about 18" across). If the creature smells rotting flesh, it extends its body out of this near-flat disc, which looks like a long accordionlike worm with a maw of four tearing hooks beneath its foreskin-like hood. The Circle-Larva advances by literally hopping its round base forward, which is a very slow and clumsy way to move. Once they settle close to a large piece of carrion they feed with violent tearing and mulching, leaving very small eggs attached to the bones which eventually hatch into tiny droplet-like baby larvae. If a Circle Larvae survives long enough it burrows into the earth and grows into its final form, which is rarely seen and highly deadly.
Circle Larvae will attack anything that approaches a feeding-ground, but they are slow and clumsy on the move. Once rooted to the ground though, their long bodies can strike with fast whiplike motions. Thunderfolk treat them as target practice, shooting larvae by the dozens from a safe distance with arrows. This is considered a good exercise for children. Their slightly gelatinous, putrescent bodies are not used for anything, but occasionally their four-bladed beaks are harvested for ornaments, or ground up for a male virility enhancement (one look at the Larva-Worm will explain why it occurred to someone this might work).
The Curse Phoenix is a skeletal bird wreathed in flame that is a kind of locally feared undead. It is believed to embody the spirit of a grassland or patch of turf that was burned out of its season, due to warfare between bands (starting brushfires is a common area-denial tactic) or to create a better topsoil for short-term planting. It typically terrifies by spitting fireballs and catching other grass fields on fire with its sweeping tale of flames. Every Curse Pheonix has one potent curse. According to legend it will deploy the curse on the one who slays it, but in fact it often starts fights by dropping its curse on an unfortunate victim. Once the recipient of the curse dies, the Curse Phoenix regains the use of its curse.
1. Partially-Eaten Grove of MERCURY BERRIES
2. PHASE-OXEN peacefully munching on a grove of MERCURY BERRIES
3. THUNDERFOLK peacefully munching on a grove of VIOLET GRASS. Several CANOPY OWLS lurk just out of sight, waiting to attack.
4. A migrating band of PHASE-OXEN, the adults keeping watch. Several CANOPY OWLS lurk just out of sight, waiting to attack.
5. A MANTICORE-SCORPION is wrorrying at a slowly dying THUNDERFOLK.
6. Several MANTICORE-SCORPIONS are chasing a couple CANOPY OWLS away from a fresh-killed PHASE-OX.
7. A slowly dying MANTICORE-SCORPION. Its flank bears the unmistakeable marks of a CURSE PHOENIX. A couple of VILE URCHINS are already beginning to pick at it.
8. A band of CANOPY OWLS that hasn't eaten in a couple of days.
9. An unrecognizable mass that used to be a THUNDERFOLK. It's being torn to shreds by a dozen CIRCULAR LARVAE.
10. A small cave which a couple of small VILE URCHINS are making a den in.
11. An enormous VILE URCHIN that follows the PCs from afar.
12. A CIRCULAR LARVA nesting site. Contains a couple of adults, a number of babies and bones.
13. A band of MANTICORE-SCORPIONS fleeing a CURSE PHOENIX, which will arrive in a couple of rounds.
14. A CURSE PHOENIX that hasn't eaten in a couple of days.
15. A panicked PHASE-OX trapped in a grove of VIOLET GRASS. A CURSE PHOENIX is somewhere in the area and the PHASE-OX can sense it.
16. A slowly dying CURSE PHOENIX, taken down by a maddened band of THUNDERFOLK. A number of CIRCULAR LARVAE are waiting for it to die properly before they approach it.
17. An UMBRAL CHILD performing cruel and mysterious experiments on a PHASE-OX. It will take no notice of the PCs.
18. An UMBRAL CHILD standing perfectly still and silent. If the PCs get within 10', it will attack.
19. A curious band of CANOPY OWLS sniffing at an UMBRAL CHILD, which pays them no heed. The CANOPY OWLS will see the PCs as easier prey. The UMBRAL CHILD will watch with interest. It may intervene on either side.
20. An UMBRAL CHILD collecting samples of MERCURY BERRY. It will assume the PCs are also plants and try to collect them as well.
landmark encounter: Rival Adventuring Party
landmark encounter: A lone traveller, trapped in a high or otherwise defensible place by a band of MANTICORE-SCORPIONS. She has been there for days and is very hungry. Will reward you for rescuing her, as for escort back to civilization. Is evil.
The Singing Ravine
landmark encounter: Resting place of a gypsy caravan and their tame herd of PHASE-OXEN (unless they themselves are PHASE OXEN???!!!) Have codes of hospitality but take them less seriously than they pretend.
The Ghost Barrens
landmark encounter: Hermit's hut. Isolated, surrounded by elaborate series of ditches, pit graps with colony of VILE URCHINS lurking at bottom. Hermit regularly feeds them, is a wizard maybe.