Lux Tenebra, the Balance

Flying, indestructible
As long as your devotion to white and black is less than seven, Lux Tenebra isn't a creature.
Whenever a creature dies, its controller may pay
3 life to return it to their hand. If another player
uses this ability, you may gain 3 life.
"I exist to bring light to the darkness. I exist to cast a shadow over the light."