Eldra, The Everlasting

Flying, lifelink, haunt (When this card is put into a graveyard from play, remove it from the game haunting target creature.)
Sacrifice Eldra, The Everlasting: Eldra, The Everlasting deals 1 damage to each opponent.
When the creature Eldra, The Everlasting is haunting leaves the battlefield, return Eldra, The Everlasting to the battlefield under your control.