Avra, Mother of Souls

Flying, indestructible
Whenever a nontoken creature an opponent controls would die, instead exile that card, and
put a +1/+1 counter on Avra.
{3}{w}{b}: Target creature gets -X/-X until end of turn, where X is equal to Avra's power.
This is not the world as I left it. As I gave life to this world, now I shall take it back.