Void Demon

At the beginning of your combat phase draw a
card and put a +1/+1 counter on Void Demon.
When Void Demon enters the battlefield target
player loses the game unless they discard a card.
Whenever Void Demon is untapped players
with 0 cards in hand lose the game.
At the beginning of each combat step any
opponent may discard a card. If a player does,
tap Void Demon.