Yveltal, God of Darkness

Flying, Lifelink, Hexproof
In addition to Yveltal, God of Death's mana cost, pay 3 life to cast it.
When Yveltal, God of Death Dies, you can pay {x}{b}{b}, then place it back on the battlefield with X +1/+1 counters. If Yveltal, God of Death dies with a power of 20 or higher, exile it, then destroy all non-black permanents of the battlefield, and you gain life equal to the number of cards destroyed this way.