Terrella, Eldritch Patrician

When Terrella, Eldritch Patrician enters the battlefield, you become the monarch.
Flying, lifelink, menace
Whenever you gain life, if you are the monarch,
mill that many cards, then you may put target permanent card from your graveyard on top of
your library. If you aren't the monarch, the
player who is the monarch loses that much life.