Kayn the Shadow Assassin

+2: Destroy target creature. If the creature destroyed this way had less power than Kayn the Shadow Assassin's loyalty, you may activate this again.
-3: Return target creature you control to its owner's hand put a creature you control from your hand onto the battlefield.
+10: You get an emblem with "Whenever you destroy an opponent's creature, put a creature from your hand onto the battlefield tapped."