Night Hunters (I'll change it if I come up with better options)
The idea is that they are the Ashan equivalent of the Wild Hunt – ghosts that fly across the sky on the longest night of the year, searching for warriors worthy of joining them. They gather an army to fight against Kha-Beleth and the Dark Messiah.
The Hunters are the reconnaissance force of the ghost army, flying ahead of the undead battle group (which I will create someday).