I would ask the mobs be marked and killed following an order... example Skull -> X -> star etc etc and ask the grp to please follow this order ;p sumtime if they dun follow hard oso

that way i will build agro on then with the normal stuff TC, demo shout, sunder, sunder, sunder, revenge, sheild slam, change target, repeat. Getting a sheild spike for your sheild while tanking multimobs helps.