Quenyah Heart Taker

"I don't give an orc's hide where you want to go. You could go to the Temple for all I care, but you'd still better be home by sundown if you like keeping your your rib cage in tact."

— Elven mother

Summary

All across and under the world, elves tell stories of a spirit which has haunted their race for uncounted millennia. As wildly different as the many elven cultures are, and as much as their origin stories vary, one thing which suggests a common ancestry is a universal character of myth referred to as "the Heart Taker".
In the region around the Roaring Lake, the Yoxchopan elves call this spirit Quenyah.
The Yoxchopā believe that their gods dwell within their cities and towns. When night falls and these places are said to sleep, so too do the gods rest their eyes and doze (this is why it is said that only villains prefer the night). This is when Quenyah hunts, for it is known that above all else he hates the gods.
Quenyah is said to take the form of a spectral minotaur, wearing a cloak of hideous hides. Some say the hides are of his own kin, others say the skins were flayed from his gods when he killed them. His right fist drips with blood, and in his left he carries a sack.
All Yoxchopā children fear Quenyah's sack, and any who brazenly claim they're not afraid of "fairy tales" are called liars and fools. The sack is why Quenyah's fist drips with blood. It is why children sprint home at dusk, and why even many adults stay indoors if they can. For Quenyah collects elven hearts in his sack, and will rip them from out of any elf he catches, still beating.
This is why Quenyah hunts elves, for it is known that second to the gods, he hates the fair folk.

"I sure can promise that the minister won't wake up in the morn, but it'll cost an extra twenty percent. Sack insurance."

— Xopotl Three-Dagger, before the murder of Itatlan's Minister of Coin

Variations & Mutation

The name and form of Quenyah varies from culture to culture. Western tree-elves call him Hengare, and though still a minotaur, he plays the role of trickster, always hatching schemes to trick people into giving up their hearts (he inevitably fails, teaching children to always be more clever than their opponents). Even the sea-elves, who are only recently reunited with their terrestrial elf kin yet have no memory of them, speak of Groomaar, a demon whose presence is heralded by deathly cold. It is said that he will force so much water down his victim's throat that their heart will burst out of their chest.
The Yoxchopan high-elves believe Quenyah sought his own divinity and killed his gods to gain it. But this sin was too great, and the act damned him for an eternity of unrest. Contrariwise, the southern plain-elves say that he instead sought to kill all gods but his own, who then punished him for bringing mortality to their divine realm.