In Native American folklore, deer and all forked-horned animals symbolized dangerous psychic and spiritual powers that had a double nature. By observing this creature, humans learned to hide when being hunted.
This piece puts me in mind of the Kalb's dark warriors, tormented by their own souls, gathering in the shadow world, awaiting his command. (The LightBridge Legacy Book III) ✦✥✦ Art credit (?): Assassin's creed artwork - Killer by Yuan