The combination of HP Regain Armor and Dog/Cat Ninja Form along with a Smoke Bomb is the only problem here.
You can knock them out of form and Gank them, its all 3 combined thats the Problem, that and the Pets usually Guarding that hinders the EQ to finish him off.
Smoke Bombers can be killed, Ninja Dog/Cat form can be killed, ppl in max HPR Armor can be killed, Stealth Tamers can be Killed, Combine all in 1 and it's a tad rediculous, but can still be done with enough of the right ppl...... doh he self Rezzed... whoops gotta start all over again.....