Thistle Jack

Thistle Jack, Hollow-Eye (also written Thistlejack) is a four-armed creature with a hollow eye, released when the party opened the sealed door of the Conservatory of Necessary Wildness in Rillachor and killed the giant who guarded it, a guardian furious that Jack had been let out. A tent camp nearby had housed humanoids paid "to keep Jack here", who had written "Is this evaporation worth it". Jack is not corrupted, which is somehow worse; his containment was wired to the power of Rillachor's stargate, and he has been heard playing notes on it as if trying to dial.

On his way out Jack touched every member of the party (lips, eyes, teeth, hands, an ear) and leaves notes with drawn faces, one of which appeared in Slick's pocket. The rules the party has gathered: He comes when we look. Don't let him count your teeth. The baby isn't crying right. Four hands, no kindness. Mum says dolls don't breathe. Rainclaw slapped him in the Hall of Navigators, and his blood tastes of mulled wine; Slick kept a vial. Soon every child in Sandwater Slough was singing a nursery rhyme about him ("Thistle Jack, Hollow-Eye, came where children shouldn't lie…"), and everyone seems to remember him.

Far to the west, in Ashwell, every party member, even those who don't dream, dreamed of Thistlejack: a memory inserted specifically into each of them. Captives of The Guild of Harrow knew of him, and in Hysteria Slick learned that Thistlejack is also the blood of an ancient fey, a substance with a cocaine-like effect on hell-touched creatures; nightly droplets ward off bad dreams, and it cannot be replicated.

Thistle Jack is all of these at once: a being, an ancient fey, and the substance distilled from his blood. The nursery-rhyme horror, the dream-visitor and the warding drug are one and the same. The party considers itself responsible for rebuilding his cage.