Like the one you'll see a bit later, Dominaria United Zur is an enchantment-matters card through and through
your Snarling Gorehound is a good boy, right
Whenever equipped creature attacks, tap target creature defending player controls and put a stun counter on it
Beyond those three, its anyones guess, but Ive been through the list of available mechanics and keywords to pick out what seems the most likely: Battlecry A Go Wide strategy is likely given the huge armies and battles in the series, and battlecry is a way to help break stalemates
Horizon Boughs ( Plane - Pyrulea ) cropped art by Jean-S?bastien Rossbach
Later, you can win with your black win conditions, like Gray Merchant of Asphodel, Exsanguinate, or Torment of Hailfire