Kami of Mourning 
Creature — Spirit
Whenever this creature enters, target creature you control or creature card in your graveyard perpetually gains "Whenever a creature you control with greater mana value than this card dies, return this card from your graveyard to the battlefield tapped."
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL