Horror Duck

Horror Duck's power and toughness are equal to the number of cards in all graveyards.
Whenever you cast a spell, opponent mills 5 cards, you gain 2 life and you may draw 2 cards.
All Horrors you control have +2/+2 and menace.
Flying, Vigilance, Trample, Indestructible, First Strike, Lifelink, Flash
{x}, Create X 1/2 Duck creature tokens
{x}{x}{t}: Target player discards X cards