Ego homini Lupus. I am the Wolf of man. That had been his motto for decades, a supernatural predator of mankind, a terror that hunted anyone without remorse, trading blood for coin. The Mark he'd been branded with had cemented himself as something apart from humanity, and able to enforce his will upon the world.
And with that Mark, Daud began to be drawn further toward the otherworldly. He could feel where the Void left its impressions, and spilled into the world- the calls of whales long dead etched into their bones as runes, the ever persistent death rattling hum of bonecharms, the whispers of the Void that spoke in unfamiliar tongues whenever he, or anyone else, used a power.
Daud felt the pull even now- but something adjacent to the Void, not begotten from it. Still, undoubtedly, black magic.
Never one to let a mystery go unsolved, Daud, against the inner judgement screaming at him of the obvious danger, followed the call and broke from his patrol route.
The figure of a man, but much taller, and broader than any man Daud had ever seen, with unusual pallor and sharp, wolfish features. His facial hair neatly trimmed, and the hair of his head cut a smart length above the shoulder, and adorned in fine cloth obscuring the physique of his body.
No, this wasn't human, and the stranger's words confirmed as such. A human wouldn't have noticed his perch without looking, and not in this darkness.
Against every instinct, Daud rises from his crouched position, and calls out: "No challenge."
He steps forward, and lets himself fall from the gantry overlooking the waterfront, waiting until he was two body lengths from the ground. He clenched his fist, feeling the Outsider's Mark burn him with a coldness and time stop as he plotted his landing. When he releases his fist, his body disappears, leaving only a cloud of black ash in his wake that quickly dissipates. Daud reappears less than the span of a blink closer to the stranger- but far enough away to give himself time to react if the conversation turned sour.
"Just curiosity," he says.