For knights, try to chase it to a corner to trap it because of its speed and use Fierce Berserk if you have too many summons hitting you. It's easier to team kill with a knight trapping with while paladins or mages shoot from a safe distance. A lvl 70 paladin can solo this monster with few strong mana potions and strong health potions. 80+ distance recommended. Solo mage's should not attempt one of these before level 60 and should use strategy to try and kill them. Try to trap it in a corner and kill it with Flame Strike or use walls or other obstacles to try and get it to come closer to you. In places such as Cemetery Quarter becareful not to run them into other groups of creatures!