Doppelgänger law:
Doppelgängers, also known as Shadow Selves or Mortal Shadow Selves. They are a double of the person who has lived before them. They were created to balance nature, by being a mortal counterpart of the true immortal being, to live and die in their place.
Doppelgängers are often known for terrorising the lives of their shadow self. Often taking over or completely destroying the lives of their shadow selves existence.