Eclyptor

It moves through the deepest night like a piece of the sky that has come loose, and where it passes the temperature drops and small ghosts scatter in deference. Its signature howl can be mirrored back at a foe, a strange echoing skill that turns a creature's own fear against it. It is thought to feed on moonlight itself, dimming when clouds cross the moon and blazing when they clear, and the very oldest Pawbury records claim that an Eclyptor appears at the deathbed of anything large enough to matter, not to harm, but simply to see it off into the dark.