Assassin tank is the best tank IMO, problem is, hes quite weak in the early levels, because on early lvls you tank with your armor mitigation, which assassin doesnt have that high. When you get on the higher levels, youll get +20% shield buff, some absorbtion buff. You will basically have the highest avoidance of all tanks + you will HEAL yourself, which makes up for the missing armor mitigation. Weve raided through all the content and our healers say that its really easy to heal Assassin, hell they can even leave him for a few seconds without heal.....