Northern's shoulders rose and fell as his eyes pierced into the subtly clearing cloud of dust. Even he could not tell if the creature had been totally eradicated with that attack.
Combining Chaos and Void was something he had always thought about, but he had never met an enemy strong enough to make him use it. In this battle with the Dark Seer, he had in fact considered using the true nature of Chaos Flame which eradicated the existence of monsters completely.
...Making it as though they never existed.
But he decided not to—no other reason than because he wanted to gain rewards for what he killed, especially now that he had the privilege of gaining items. It was not like Ul had oversight over this place anyway. Because if Ul did, he definitely wouldn't be getting items.