They wander dark, forgotten places tainted by magic, hiding above their prey at night, in trees and buildings like some kind of spider. They do terrible things to those they catch but for some reason detailed memories pertaining to them simply fail to form, if one is so lucky to survive. You know it's attacked you, but you don't know how or when, you always know what they did, but never the exact actions themselves. Even after the encounter, you feel as if you're being watched and hunted. . .