I don't know! Last time I saw a real ghost one of my friends lit it on fire and that seemed to work pretty well, but I kinda feel like that's not an option in here.

[ Even if he had any elemental flasks on him, it sounds like being here would've rendered them inert. Plus this house is pretty small and full of things that'd probably burn as well as or better than a ghost. ]

Maybe try to hit it with something heavy if it shows up again? Whatever we do, we absolutely should not split up. That's always when they get you.