Limited Reincarnation

In lands observing this Law, entities residing on that land full time may reincarnate themselves into another type of entity residing on the same land, as long as their soul is strong enough.
Law originates from Disgaea. Prinnies can reincarnate as monsters or humans with professions, but the professions or monsters have to be already unlocked in order to pick it. Different games in the series have the unlocks happen different ways, so I (Viirin) am saying one citizen makes a new unlock. Like, if you get a monster from Monster Hunter as a citizen somehow, and a citizen that's a necromancer that's from somewhere else, you can have a character with no profession (for example) reincarnate as a necromancer, or have a doll citizen reincarnate as another of your Monster Hunter monsters.