I was curious, would the final blade work on a lich? I'm thinking because it has already trapped its soul in a phylactery it probably wouldn't but the Final Blade is a minor artifact. Would it be able to overcome the necromantic magic?
Yeah, but would the Lich still be good to go with the Final Blade acting as his phylactery or would that cut them off from their soul and kill them good?
That would be a GM call, a Lich possessing the weapon and turning it into its new phylactery would make for a cool story, but most likely it would trap the Lich's soul so the moment they're destroyed they're screwed.