In the mist-wreathed borderlands of a Celtic-inspired realm, the Mistwood hides glades where the fey court keeps watch and hag covens weave mischief. A centuries-old linnorm, serpentine and storm-wraught, slumbers beneath the river’s depths, its heart bound to a hidden rite. Three covens—the Green Hag, the Autumn Hag, and the Night Hag—seek to awaken it, using a ritual called the Knot of the Harrow Moon. If the linnorm stirs, forests burn with bracken, crops fail, and towns near the border fall to feverish dreams and shadowed omens. The players are drawn by a desperate druidic circle, a bereaved noble, and a pixie troupe whose songs make folk forget to fear; each begs them to intervene before the rite completes.

Main quest: uncover and unite three sacred totems that anchor the veil between worlds, then perform a counter-ritual to bind the linnorm’s heart and seal the fey-waking power. The totems lie in three perilous sites:
- The Hollow Birch Gate, a living arch guarded by woodland guardians and riddle-walkers who test what a hero believes to be true.
- The Choir of Echoing Stones, a ring of standing stones whose voices reveal secrets only when sung back by the entrant.
- The Laughing Well, whose waters reveal truth at a cost and grant glimpses of futures the party may be forced to choose between.
Each trial requires wit, courage, and a sensitive alliance with a fey ally who can aid the party without betraying them to the covens.

Act structure and central events: Act I establishes the Mistwood’s cadence—watching hawthorn, fey lanterns, and hag whispers—while the players locate the totems and thwart minor awakenings. Act II threads cooperation with select fey factions and a dangerous alliance with a morally ambiguous hag who seeks to break the Knot differently. Act III culminates at the Linnorm’s lair beneath a ruined shrine, where the party must outmaneuver the covens, decide whether the linnorm is slain, bound, or perhaps re-enslaved to a wiser power. The Harrow Moon cycle triggers periodic shocks: tremors in the earth, sudden fogs, and a final eclipse that compresses all choices into one decisive action.

Hooks and side-quests: rescue of a vanished choir who can sing the truth back into people, retrieval of the Lullaby Bell that pacifies the linnorm but ferries mortal memories away, and a mission to free a captive sprite court from hag dominion.

Rewards: allies among the fey who grant boons and favors, relics attuned to nature, and the life-sustaining magic of the totems—each offering the party a unique blend of protection, utility, and narrative leverage.