Griselbrand, The Vengeful

Flying, Lifelink, Punish, Deathtouch, you have no maximum hand size
Bond: Demons you control have: Pay 1 life: Draw 1 card and add {b} to your mana pool. They also have lifelink and flying.
Pay 7 life: Draw 7 cards
Pay 10 life: Discard 10 cards and deal 10 damage to your opponent
Pay 20 life: You win the game (Must have more than 20 life, if any source of damage at instant speed would kill you, you lose instead)