Focus on killing the minion Horsemen using the many area of effect cards that you have. The Voidwalkers are very powerful so play those as early as you can.
Play as many taunt minions as you can since it accelerates killing the minion Horsemen. Lord Jaraxxus is a good finisher since he has 15 health and gives you a weapon. Make sure that when you kill the last minion horsemen that you can kill Lord Rivendare within a turn since his weapon will be buffed.