Echoes - Bestiary

The Fae Manual

A folklore compendium & working game taxonomy of the Celtic Otherworld.

How to read this (and an honest caveat)

There is no single canonical Celtic fairy taxonomy. What follows is synthesised from Irish, Scottish, Welsh, Cornish, Manx and Breton folklore - traditions that overlap but disagree on names, natures, and which beings even count as "fae." Much of the familiar categorisation comes from later folklorists, not ancient sources. I can't verify these details against live sources, and folklore varies wildly by region and teller, so treat this as a designer's working draft to confirm, not authority.

The disagreement between sources is the point - see §1. Where the popular image is demonstrably modern (pointed ears, butterfly wings, tiny size), I say so - not to forbid it, but so you fold it in on purpose, as one attested "account" among many.

(Standard references worth checking, but I can't guarantee I've remembered or cited them correctly - verify before relying on any: Katharine Briggs, A Dictionary of Fairies; W. Y. Evans-Wentz, The Fairy-Faith in Celtic Countries; W. B. Yeats, Fairy and Folk Tales of the Irish Peasantry; James MacKillop, Dictionary of Celtic Mythology. Turn on web search and I can pull verified specifics and real sources.)

Pronunciations are rough English approximations - Gaelic and Welsh orthography doesn't map cleanly, so confirm if it matters.

1 · The Many-Accounts Principle (our design philosophy)

Celtic fae are described a dozen contradictory ways across regions and centuries. Rather than flatten that into one "correct" version, we treat each surviving account as a distinct in-world manifestation of the same lineage. A Tylwyth Teg attested as tall and fair and attested as a winged mote becomes two recognised forms of the same kindred in our world.

Why this serves the game:

Model variety. We never recycle one fairy mesh across the whole game; each kindred ships several distinct forms.
Story utility. Different forms serve characters differently - a winged fae can scout, carry, or lure where a courtly one negotiates.
Rarity as meaning. When a region's fae are mostly wingless, the single winged one - or the only one that glows, or bears complex markings, or stands a head taller - reads as special, ancient, or dangerous without a word of exposition (see §8).
Richness = believability. A world whose background teems with variation feels lived-in and real, which is pure fuel for storytelling.
Not all fae are humanoid. Many are animals or hybrids (water-horses, fairy hounds, seal-folk, goat-women, serpents). We lean into that - see Kindred VIII.

So most entries below carry a ▸ Variants line: the spread of forms that lineage can take in our world.

2 · Variant Axes (the generative vocabulary)

To build or vary any fae consistently, turn these dials. They double as a model-brief checklist.

Form - humanoid · animal · hybrid (part-beast) · elemental/incorporeal (mist, light, water-shape).
Scale - towering (god-remnant) · human-sized · diminutive (knee-high) · mote (hand-sized).
Wings - none (traditional default) · feathered · insectile/gossamer (modern, embraced) · membranous · "false" (a glamour of wings).
Luminosity - mundane · faintly glowing · radiant · spirit-only (invisible to mundane sight - ties to the spirit-sight register).
Markings - plain · knotwork-marked (Insular interlace on skin/hide) · heraldic (Court sigils) · scarred/branded.
Temperament - Seelie-leaning (proud, fair-dealing, vengeful if slighted) · Unseelie-leaning (malevolent) · amoral force-of-place.
Register of being - what it seems vs what it is (its glamour and the truth beneath). Author both.

A single kindred can occupy several points on each axis; that's how one folklore name yields a family of models.

3 · Origins & Genealogy - where the fae come from

Competing origin-stories, none exclusive; any can seed your tree:

The Diminished Gods (the central Irish thread). In the Lebor Gabála Érenn (Book of Invasions), the Tuatha Dé Danann - the god-race - are defeated by the Milesians and withdraw beneath the land into the sídhe (mounds and hills), shrinking over generations into the Aos Sí, the fairy folk. This is your genealogical spine - and it's already wired in, since the Tuatha de Danann are a player tribe. It implies the high fae and that tribe are kin, or that the tribe descends from those who refused to fade.
The Fallen-but-not-Damned. Folk-Christian gloss: angels who fell but weren't wicked enough for Hell - caught in the between. Suits "forces, not foes."
The Dead / the Ancestors. Many fae blur into the restless or honoured dead (the Sluagh; Tech Duinn, the house of the dead). Fits your soul-and-rebirth cosmology.
Spirits of Place & Element. The oldest layer - fae as the genius of spring, stone, bog, tree; older than the courtly Sídhe.

Otherworld realms: Tír na nÓg ("land of the young"), Mag Mell ("plain of delight"), Tech Duinn ("house of Donn," of the dead) in Irish; Annwn, the Welsh Otherworld (Arawn / Gwyn ap Nudd). Reached through mounds, mists, under water, over the western sea, and at the turning festivals.

4 · How to group them (the axes)

Pick a primary axis for the game; keep the rest as flavour.

By Court - Seelie vs Unseelie. Lowland Scots, not pan-Celtic. Seelie ("blessed"): proud, fair-dealing, vengeful if slighted. Unseelie: actively malevolent. A clean two-faction spine - just a borrowed regional one.
By Sociability - Trooping vs Solitary. Yeats's Irish division. Trooping fae move in companies, hold revels and processions (the "fairy rade"); solitary fae live alone, bound to a craft, place, house, or omen.
By Domain. High court / death / hearth / water / stone / wild / beast - the structure of §5, mapping best onto your biomes.
By Lineage. Diminished gods vs spirits-of-place vs the dead - best for a literal family tree (see §9).

5 · The Kindreds (catalogue)

KINDRED I - The High Folk (the courtly, human-like Sídhe)

The lordly fae: tall, beautiful, regal, dangerous because they seem civilised. Your "tall, fair, beautiful faces."

Daoine Sídhe (DEE-nuh SHEE) - Irish; "people of the mounds." The aristocratic race, the diminished Tuatha Dé. Also Daoine Maithe, "the good people" (a flattering euphemism - §7).
Tylwyth Teg (TUHL-with TEEG) - Welsh; "the fair family/tribe." The Welsh fae broadly - an umbrella term, which is why it spans so many forms.
The Gentry - Irish (esp. Sligo/Yeats) for the tall, noble fae who must be addressed with respect.

▸ Variants (in-world manifestations): the Fair Lord/Lady (tall, golden, wingless - the courtly default); the Winged Noble (radiant feathered or gossamer wings - the "modern" image, embraced here as a high-rank or messenger caste); the Trooping Mote (diminutive glowing forms that swarm in procession); the Marked Elder (knotwork-scarred, ancient, half-faded toward spirit). Same lineage, four models, a built-in hierarchy.

KINDRED II - Heralds of Death & Ill Omen

Bean Sídhe / Banshee (ban SHEE) - "woman of the mound." Keens to foretell a death, bound to certain old families. A messenger, not a killer.

▸ Variants: the lore explicitly gives her three ages - radiant maiden, grave matron, terrible hag - a ready triune-model set echoing your Morrigan's Badb/Macha/Anu.
Bean Nighe (ban NEE-yuh) - Scottish; "the washer woman" at the ford, washing the grave-clothes of the soon-to-die. Catch her and she may grant wishes.
Dullahan (DOOL-a-han) - Irish; headless rider bearing its own head; where it stops, someone dies. Repelled by gold.
Sluagh (SLOO-ah) - "the host." The restless, unforgiven dead, flying in a dark flock from the west to seize souls. Keep west windows shut.
Leanan Sídhe (lan-AWN SHEE) - "fairy sweetheart." A muse-lover granting brilliant inspiration for life and devotion; the artist burns bright and dies young.
Fear Gorta (far GOR-ta) - "man of hunger." A gaunt famine-spirit walking the land in lean times; charity to him brings luck.

Game hook: slots straight into the essence/soul economy and Raven's-Sight death-timelines.

KINDRED III - Hearth & Household Spirits

Bound to a home or farm; help in secret; ruled by etiquette.

Brownie - Scottish/Border; labours by night for cream and bread. Offer it clothes or wages and it leaves, offended forever.
Bwbach / Bwca (BOO-bakh / BOO-ka) - Welsh household sprite; helpful, touchy. (Also counted under Tylwyth Teg - the umbrella again.)
Gruagach (GROO-uh-gakh) - Scottish guardian of cattle/farm; sometimes brownie-small, sometimes a grand spectral figure left libations of milk.
Fenodyree (fə-NOD-uh-ree) - Manx; a hairy, strong brownie-type.
Clurichaun (KLOOR-i-kawn) - Irish; solitary cellar-cousin of the leprechaun, keeps the drink (or drinks it).
Leprechaun (LEP-ruh-kawn) - Irish; solitary shoemaker guarding hidden gold; bargains for freedom if caught. (A craftsman, not the mascot.)

Game hook: perfect for your reciprocity rules - favours that flip to curses the moment a taboo (thanks, payment, intrusion) is broken.

KINDRED IV - The Water Folk

Of bog, loch, river and sea - often the deadliest, and frequently non-humanoid.

Each-uisge (ekh-OOSH-kya) - Scottish/Irish "water horse"; lures riders, then drowns and devours them; skin turns adhesive. Among the most lethal in the lore.
Kelpie - Scottish river-horse; haunts fords and pools.
Merrow / Murúch (MUR-ookh) - Irish merfolk; females beautiful, wearing a cohuleen druith (red cap) without which they can't return to sea.

▸ Variants: accounts split sharply by sex - beautiful maiden-merrow vs grotesque male merrow (green skin, sharp teeth, pig-like). Two very different models, one kindred.
Selkie - Orcadian/Scottish (Norse-tinged); seal-folk who shed skins to take human form; steal the skin and you bind one ashore.
Gwragedd Annwn (GWRAH-geth ANN-oon) - Welsh "wives of Annwn," benevolent lake-maidens who may marry mortals under strict taboo. (Also Tylwyth Teg.)
Glaistig (GLASH-tig) - Scottish; grey half-woman / half-goat of water and stone - ambiguous: protector of cattle and children, or blood-draining lure.
Fuath (FOO-ah) - Scottish; a category of malevolent water-spirits (the Each-uisge and others fall under it).

Game hook: your Whispering Fens are built for this kindred - drowned-beast bargains, lure-and-drown horror, the red-cap-as-anchor object.

KINDRED V - Stone, Mine & Mountain

Coblynau (kob-LUH-nai) - Welsh mine-spirits, the "knockers," half a yard tall; their knock marks rich seams (or warns of collapse). (Cornish kin: the Knockers.)
Gwyllion (GWUH-thlee-on) - Welsh hag-like mountain spirits leading travellers astray; afraid of iron knives.
Bodach (BOD-akh) - Scottish/Irish old-man bogey of hill and chimney; a fright to children.
Ghillie Dhu (GHIL-ee DOO) - Scottish; shy solitary guardian of birch woods, clothed in leaves; kind to lost children.

Game hook: your Iron Crags + Fir Domnann smiths build in friction - miners who live by iron courting earth-fae who fear iron. "Knock = ore / knock = doom" is a ready mechanic.

KINDRED VI - Tricksters & Shape-Shifters of the Wild

Púca / Pooka (POO-kah) - Irish shapeshifter, helpful or malicious; tied to Samhain (after which it fouls the blackberries - none may be eaten).

▸ Variants: the shapeshifting is the variant set - black horse, goat, hound, hare, eagle/bird, or a dark goblin-man. One named being, many forms; perfect for the whimsical trickster energy of your rebirth-giver.
Fear Dearg (far DARG) - "the Red Man," a solitary prankster in red cap and coat; grim jokes; his goodwill brings luck.

KINDRED VII - The Wee Folk (and the embraced winged forms)

Ellyllon (eth-LUH-thlon) - Welsh; diminutive elf-like spirits of groves, feeding on toadstools and fairy-butter.
General "wee folk" - the small, swarming fae of hedge and field.

▸ Variants: this is where we deliberately house the winged sprite (gossamer, glowing motes) - a modern image we adopt as the minor diminutive register, kept distinct from the wingless, human-scaled nobility of Kindred I. Mixing the two (wingless lords vs winged motes) reinforces the hierarchy rather than muddying it.

KINDRED VIII - Beast-Fae & Hybrids (the non-humanoid)

Fae closer to animal than person - for model variety and uncanny non-human encounters. (Several beasts already live in IV and II - the Each-uisge, Cù Sìth, Cŵn Annwn, Merrow, Selkie, Glaistig.) Additional:

Cat Sìth (kaht SHEE) - Scottish/Irish; a great black fairy cat with a white breast-spot; said to be a witch transformed, or fae; tied to Samhain rites.
Cù Sìth (koo SHEE) - Scottish; "fairy dog," huge and dark-green; a death-omen that bays three times.
Cŵn Annwn (koon ANN-oon) - Welsh; spectral "hounds of Annwn," coursing the sky with the Wild Hunt to gather souls.
Crodh Sìth (kroh SHEE) - Scottish; fairy cattle, often hornless and dun, of great milk-yield, rising from lochs.
Tarbh Uisge (TAR-av OOSH-kya) - Scottish/Manx; the water-bull, less malevolent counterpart to the water-horse; may sire calves on mortal cattle.
Adar Llwch Gwin (AH-dar thlookh GWIN) - Welsh; giant magical birds (griffin/falcon-like) that obey a master's command.
Beithir (BEH-hir) - Scottish Highland; a great serpent / wyrm of caves and corries - venomous, deadly even when cut. (Bridges directly into the Wyrm & Dragon Bestiary.)

▸ Variant principle applies: any beast-fae can be given a singular standout (a knotwork-marked Cat Sìth, a glowing white Cù Sìth) per §8.

6 · Rulers & Courts (named nobility for your genealogy)

Finvarra / Fionnbharr (fin-VAR-ah) - King of the Connacht fairies (Knockma); sometimes king of the dead; chess-player, horse-lover, seducer of mortal brides.
Áine (AW-nyuh) - Fae queen/goddess of summer, sovereignty, love, fertility (Knockainey); a bridge between goddess and fairy-queen.
Cliodhna (KLEE-nuh) - Queen of the Munster fae, a banshee-queen; beauty, the sea, three magical birds.
Midir - a lord of the sídhe of Brí Léith; the love-tale of Midir and Étaín.
Donn - lord of the dead at Tech Duinn, off the south-west coast.
Gwyn ap Nudd (gwin ap NEETH) - Welsh; king of Annwn, lord of the Tylwyth Teg, master of the Wild Hunt and the Cŵn Annwn. A natural dread-patron or high antagonist.
Arawn - earlier Welsh king of Annwn (the Mabinogi).
The Cailleach - the winter-hag/sovereign-crone who looms over the seasons.

7 · The Laws of the Fae (cross-cutting - and pure mechanics)

These recur across every tradition and map almost one-to-one onto your systems:

Cold iron repels them. (Your Corani vulnerability; your Fir Domnann friction.)
Never give your true name. Names bind. (Your name/language sacrifices; the word-as-power thread.)
Never eat fairy food. Eat in the Otherworld and you may never leave.
Reciprocity is law - but charged. Gifts oblige; thanking or paying a brownie drives it off; offerings must be right in kind. (Your Contextual Materiality.)
Glamour. Seeming cloaks being - a hovel as a hall, rot as a feast. (Literally your spirit-sight register - and governed in full by the Seeming & Sight system in its own file: glamour and spectral-sight resolve on one tier ladder, so a seeming holds unless the observer's Sight outranks its Weave.)
Time runs wrong. A night's dancing is a hundred years; returnees crumble to dust.
Liminality is their strength. Dusk and dawn; Samhain and Beltane; thresholds, fords, crossroads; the fairy fort / rath / lone hawthorn - disturb those and be cursed.
Changelings. Healthy infants stolen, withered doubles left; iron, fire, and trickery expose them.
Euphemism as protection. Don't name them plainly: the Good Folk, the Gentry, the Fair Folk, the People of Peace (Daoine Sìth), Themselves, the Good Neighbours. To name a thing is to summon its attention. (A beautiful naming/kotodama mechanic - mortals speak in euphemism; the brave or foolish speak true names and pay.)

8 · Unique & Singular Fae (a design pattern for standouts)

Use the thinly-attested fae - and deliberate one-offs - as named, singular beings that break their region's pattern and so read as significant without exposition. The recipe:

Take a base kindred (or a minor/obscure fae with little lore).
Break one variant axis against its region's norm: the only winged one where all others crawl; the one that glows in a kindred of dull spirits; one twice the size; one bearing complex knotwork markings none other has; one visible only in spirit-sight.
Give it a name and a why - ancient, half-faded, a king in exile, a thing the Courts themselves fear.

What this buys you: memorable mini-bosses, quest-givers, and omens; rarity that carries meaning; and a use for the strange single-source creatures rather than discarding them. Examples to develop: the lone radiant moth-winged elder among the bog-motes; the white Cù Sìth that bays for no death but a rebirth; the knotwork-scaled Beithir whose markings are a map.

9 · Game genealogy & faction map

Turn the above into structure, mapped to your biomes and tribes.

The genealogical bifurcation (trunk of the tree):

The Faded Courts - descended from the diminished Tuatha Dé (Kindreds I, II): beautiful, courtly, glamour-wielding, bargain-givers. Kin to your Tuatha de Danann tribe.
The Elder Spirits - older than the Courts: the genius of water, stone, beast, and the dead (Kindreds IV, V, VIII, and the death-heralds of II). Not courtly, not kind - forces of place.

Biome mapping: | Region (tribe) | Resident kindreds | Friction / hook | |---|---|---| | Whispering Fens (Corani) | Water Folk + beast-fae + bog death-heralds (Each-uisge, Merrow, Glaistig, Tarbh Uisge, Bean Nighe, Sluagh) | lure-and-drown bargains; red-cap anchor; the Corani's own iron-vulnerability vs iron-fearing fae | | Iron Crags (Fir Domnann) | Stone/Mine + Beithir (Coblynau/Knockers, Gwyllion, Bodach) | the iron paradox; "knock = ore or doom"; blood-passage tolls; the serpent in the deep stone | | Sylvan Canopy (Tuatha de Danann) | The High Folk, Ghillie Dhu, Leanan Sídhe, Adar Llwch Gwin; ruled near Gwyn ap Nudd / Finvarra / Áine | the solar/noble court; glamour and the muse-bargain; the tribe's uncanny kin | | Cross-region / roaming | Púca (Samhain), the Wild Hunt (Gwyn ap Nudd + Cŵn Annwn), the Sluagh, the Fear Dearg, Cat Sìth | seasonal/festival events on your phase wheel |

Naming convention: the Court of [Realm] for noble lineages (Court of Knockma, Court of Annwn); the Kindred of [domain] for elder spirits (Kindred of the Drowned, Kindred of the Deep Stone); mortals refer to all of them only by euphemism in-world - naming a House plainly is itself a risky act.

Variant & uniqueness as a content system: every region fields several forms per kindred (for model variety) plus one or two singular fae (§8) as standouts - so no fairy is ever copy-pasted across the game, and the rare ones always mean something.

Next I can: draft in-world bestiary entries (flavour text + bargain/stat hooks per form, in the game's voice); design the glyph/sigil families per Court (tying to the runestones in your concept art); or build the genealogical tree as a diagram. Turn on web search and I'll verify the folklore and pull real sources before anything becomes canon. The companion Wyrm & Dragon Bestiary begins in its own file.

Wyrm & Dragon Bestiary

Welsh-centred, Celtic-broad · a working draft.

Caveats (same footing as the Fae Manual)

Synthesised from memory of Welsh, Irish and Scottish tradition, which I can't verify live and which varies by source - confirm before anything becomes canon, and turn on web search for verified detail and real citations. One framing point worth holding: Celtic dragons are mostly not the hoard-guarding, fire-breathing dragon of Germanic legend. They skew serpentine, territorial, tied to water, earth and sovereignty - forces of place and omen more than treasure-keepers. That fits "forces, not foes" perfectly, and it's where Welsh tradition (the most dragon-rich strand of Celtic myth) leads.

The Many-Accounts Principle from the Fae Manual applies here too: contradictory descriptions (crested vs scaled, winged vs legless, water vs sky) become distinct in-world wyrm forms, not problems to reconcile.

1 · What a "dragon" is here (taxonomy)

Four overlapping forms - useful for both models and how each is dealt with:

Wyrm / Worm - wingless, often legless; a vast serpent of mound, well and loch. Venom and crushing coils; regrows when cut (sever it and the parts seek to rejoin); grows without end if unchecked. The oldest, most Celtic-fringe form.
Gwiber / Wyvern - two legs plus wings; the Welsh winged or crested/feathered serpent that plagues a district until slain.
Dragon (Draig) - the heraldic four-legged, winged form; how Y Ddraig Goch is shown in later tradition.
Water-beast - lake and river monsters (Afanc, Ollphéist) - not always "dragons," but kin, and at home in your fens.

The recurring Celtic note: a dragon is a force of place and a token of sovereignty. To free, bind, or disturb one shifts the balance of land and rule - which is exactly your Law of Cosmic Balance and your Macha/sovereignty axis.

2 · The Catalogue

Welsh (the heart of it)

Y Ddraig Goch - the Red Dragon. The emblem of Wales; the sovereignty of the Britons made flesh. From the tale of Lludd and Llefelys and the Dinas Emrys prophecy (told via the Historia Brittonum and the Myrddin/Merlin legend): a red dragon and a white dragon, buried beneath the hill, shriek every May eve (Calan Mai); Vortigern's tower will not stand until they are unearthed; freed, they battle, and the red (the Britons) at last overcomes the white (the Saxons).

▸ Variants: the heraldic four-legged winged Draig (banner form) vs an older, more serpentine red wyrm (the buried, shrieking thing). Two registers of the same icon - a noble emblem and a primal force.
The Two Dragons of Dinas Emrys - buried at the island's centre to silence their war-shriek: the buried-power-beneath-the-hill motif. (See game hooks.)
Gwiber - the Welsh winged/crested serpent (wyvern); local tales (Penmachno, Glamorgan and others) of feathered or crested flying serpents that terrorise a valley until killed, often by a trick.
Afanc (AH-vank) - the lake monster of Llyn yr Afanc; described variously as a giant beaver, a crocodilian, or a dwarfish demon - a water-beast dragged from the depths by oxen. (A clean example of the Many-Accounts Principle: pick which forms coexist.)
Carrog / Draig - general Welsh terms for dragon/serpent; useful for naming.

Irish (great worms more than dragons)

Ollphéist / Oilliphéist (OL-faysht) - "great worm/monster"; vast water-serpents of lough and river. Saint-banishing tales abound - one is said to have gouged the course of the Shannon as it fled.
Caoránach (KEE-ra-nakh) - a monstrous serpent, "mother of demons," of Lough Derg, slain or banished by St. Patrick.

Scottish / Northern Isles

Beithir (BEH-hir) - the greatest of serpents, a wyrm and lightning-beast of caves and corries; venomous, and deadly even when cut - bury the head far from the body or it rejoins. (Shared with the Fae Manual's Beast-Fae - your bridge between the two bestiaries.)
Stoorworm (Mester Stoor Worm) - Orcadian (Norse-tinged); a sea-serpent so vast its teeth became the islands (Orkney, Shetland) and its body Iceland - the apocalyptic sea-wyrm.

The broader Wyrm archetype (context, not strictly Celtic)

Lambton Worm / Northern English well-worms - wingless serpent-dragons that grow monstrous, coil whole hills, and regenerate when cut. The "worm" substrate under the Celtic-fringe serpents.
(The Germanic/Norse Lindworm is the cousin - noted only so you can place the Celtic forms against it.)

3 · Themes & game hooks

Dragons as sovereignty. The Red Dragon = the land's right to rule. Whoever frees, binds, or commands a great wyrm tilts the political and cosmic scale - a late-game lever on your sovereignty (Macha) systems.
The dragon beneath the hill (Dinas Emrys). A world-power asleep under the land; the fairy-fort taboo writ enormous. Disturbing it is catastrophe - and possibly the engine of an ending.
Wyrms can't be cleanly killed (they rejoin). This is your "forces, not foes" made literal: you redirect, bind, appease, or seal a wyrm - burying head from body, trapping it under stone, drowning it, binding it with a true name - rather than simply slaying it. A richer, more mythic boss-verb than "reduce HP to zero."
Biome seating:
Whispering Fens (Corani) → water-wyrms and lake-beasts (Ollphéist, Afanc) - coil-and-drown leviathans beneath the bog.
Iron Crags (Fir Domnann) → the Beithir in the deep stone - the miners' ultimate dread; pairs with the knockers.
Sovereignty arc / world-tier → Y Ddraig Goch and its white adversary as forces whose waking reorders the world.
Serpent-energy & the land. Treat wyrms as the concentrated power of place / ley-lines - sleeping in mounds, lochs and corries. This ties dragons into the same animistic soil as the fae and the sídhe.
Variant & singular use (per the Fae Manual §8): feathered/crested vs scaled, winged vs legless, water vs earth vs sky give you multiple wyrm models; and a singular dragon (the Red) stands as a unique world-figure, while a knotwork-marked Beithir or a glowing white worm can be a one-off omen-boss.

4 · Next steps

Per-creature encounter entries in the game's voice (how each is sealed vs slain, its toll, its omen).
A "how a wyrm is bound" system - the mythic alternative to killing (name-binding, burial, drowning, stone-sealing).
The Red Dragon as a sovereignty mechanic - what waking it does to the world-state.
Tie serpent-energy to the land/ley-lines so dragons share the animistic logic of the sídhe and the fae.
Verify via web search before canonising any tale or name.