Wraiths

The very reason Nightweald is so dangerous and so inhospitable, is because of these creatures: the wraiths. Dreadful ethereal beings, the wraiths lurk the darkness of Nightweald and assault helpless humanoid beings, transforming them into the Accursed. When facing a wraith, one will quickly notice that striking at their insubstantial body has little effect, but they have one weakness: they skull. Crush their skull and these demons will have nothing to hold them in The Mortal Realm. When they possess humanoids, their insubstantial body will slip through all material and into the body of the victim, but they cannot penetrate silver. This is why The Cleansers always wear a thin plate of silver under their leather outfit.

History
The history of the wraiths are vague and shrouded in mystery, and no one knows when they came to Nightweald. Or at least, no one remembers. Nightweald has long simply been an uncivilized forest which split The Mortal Realm in two, preventing trade from the nothern regions to the southern ones and the wraiths seem to always have been in this inhospitable, hostile forest. It is widely known that the wraiths are creations of Belin, the Netherlord of madness, and that they possess other living beings to keep themselves within The Mortal Realm. They are forced through the barrier of the Netherworld into The Mortal Realm, where they have very short time to find a wild animal as a host, or they will dissappear back into the Netherworld. If they succeed in possessing a wild animal, this animal will quickly die and the wraith will begin to warp and twist the bones of the creature, until it resembles a wolf's skull. Depending on the animal possessed, this wolf's skull can also have tusks or even horns. This skull will serve as the wraith's only link to The Mortal Realm, which is why the wraith will 'die' if the skull is crushed. And once the wraith has mounted this skull atop of its ethereal body, it will begin searching for greater prey: humanoids. If a humanoid is unfortunate enough to stumble across a wraith like this, the wraith will not hesitate to drop the wolf's skull behind and possess the unfortunate victim. If it gets this far, it will begin to change its new host into the dreadful Accursed, transforming males into werewolves and females into vampires. And when that is done and the host has been driven insane, the wraith has fulfilled its master's bidding.