The Ceyvants - spooky, scary, skeletons?

Biographical Information
Origin: unknown
Pronouns: usually it/its
Residence: Limdur

The Ceyvants are skeletal creatures of mysterious origin, and are the largest demographic of the Ceyvant Empire. They are quite intelligent creatures resembling human skeletons, though only superficially.

They require little to survive, and technically fit the definition of undead. The only thing they really need to function is an intact brain and pure Silhiya, which their bodies naturally absorb small amounts of from their surroundings. Every couple of months they need to consume a larger amount, and if they are injured they also require more Silhiya.

It is unclear how exactly they come into existence, though eyewitness accounts claim that skeletal remains can be transformed into fresh Ceyvants. While this sounds plausible, it is simply not feasible that all Ceyvants stem from corpses, as the sheer volume of their population would necessitate an extinction event of titanic proportion. No such event has taken place since or even shortly before their emergence nearly 200 years ago.

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