Xir'ain thought for a moment in his dungeon's burning heart. Could he use such a power? His immediate thinking was no; he needed living things, not dead ones. The dead and rotten would not feed his forces, and he had no enemies. But he could make enemies. No, the giant could make enemies for him. And then Xir'ain was done thinking, a beautiful, terrible plan having shaped itself in his mind. He'd decided. Between his outstretched hands, the swirling storm of black water and golden light flared with power.
The Xir'ain mimic looked only at the giant's one seeing eye. The black figure held out a hand, and a swirling storm of black and gold, not entirely unlike the one raging in the dungeon's heart but of a much smaller scale, formed between it and the giant. Ribbons of gold reached out and wrapped around the runner's ruined corpse, pulling black water into it, recreating bone and muscle and skin, but leaving the husk entirely lifeless, to be destroyed again by the giant's gaze. "There is nothing in my domain I cannot create and recreate, but the creations of others I cannot with my present power. Can your magic also stop such a plague once it has been created? It shouldn't matter either way, but it would be convenient. No, I'm getting ahead of myself. There are many steps between now and then. I haven't even presented you with your options yet."
The golden storm of lightning and water raged stronger. "Creature of rot and decay, your worlds are weak, but your body and magic is strong. In exchange for continued life, I ask of you one thing: that you accept I, Xir'ain, Keeper of the Dark Abyss, as your master, creator, and god, to obey, serve, and die for. You are free to reject my offer and die now, as your corpse would serve my intentions nearly as well."