Avada Kedavra

Destroy target creature.
Merciless (You may sacrifice a creature in
addition to the casting cost to exile target
creature instead.)
As this spell resolves, roll a six-sided die—
•1-2: Return Avada Kedavra to your hand
•3-4: Avada Kedavra gains rebound
•5-6: Place Avada Kedavra in your graveyard