Thanos, the Mad Titan

+1: Draw a card. You may discard a card from your hand, if you do, create a 2/2 black creature token with menace called "Child of Thanos"
0: Thanos becomes an X/X creature with indestructible until end of turn, where X is equal to his loyalty. He is still a planeswalker.
-7: Each player flips a coin, if it is heads, they lose half their life total, rounded up, and sacrifice half their creatures at random.