He's hiding amongst them, so all I have to do is bury or sink all of them and he'll go away forever unless someone lets him out. The NPCs themselves will probably reset or turn to shadows eventually and come back to the surface, but he'll stay down there. He's human.

[ It seemed like a simple solution to her. It might not be the most moral one, but at this point she honestly didn't know anything else that she could do. She tried destroying the system already. He just fixed it. As long as he's here, no one is safe, and she already knows she's going to lose everyone anyway so she might as well at least make it so they can choose how she loses them. ]

He better hope I don't figure out who he is before he's down there.