In most encounters where a group of players faces multiple elite mobs, the basic strategy is to have the tank hold the attention (aggro) of an enemy target while the DPS classes kill it and the healing classes keep the tank alive. Additional enemies who are active may be crowd controlled in some way to keep them from attacking the non-tanking classes, or overwhelming the tank. In a certain sense, the tank is exercising a form of crowd control itself: it's keeping a mob occupied so that it cannot attack party members with less health and armor. However, while tanks, backed up with a good healer, can often 'survive' the attacks of more than one monster, it gets increasingly difficult to keep additional mobs focused on the tank while the rest of the party is building threat with all other mon