Ok, not much info here so here's what I found.
All 3 mobs will aggro when you engage one.
There are the 3 named and 2 necro pets to fight.
3 named are low hit points. Maybe 30k ish. I just snared them all and ran around dotting them. They hit hard so don't play that game too much. Didn't kill the pets.
Solo'd them with my 70 druid, time geared, 480 aa's. Took 76% mana with 3 self heals and 2 heal pots. Could have done it with less equipment, just would have taken a bit longer. About a 12-15 minute running fight.