Zombie or Duck?

Menace, haste
{t}:Exile target creature an opponent with power 3 or less, then flip a coin. If heads, replace that card with a 2/2 Zombie creature token. If tails, replace that card with 0/1 Duck creature token with flying.
{b}{g}:Until end of turn, if Zombie or Duck deals damage to a player, that player mills that many cards.