I flagged heros/hench and went forward on dryders to draw thier [meteor shower] then release the team to finish them off. Take your time, go slowww and pull small groups. Its also benificial to watch baddies for a bit to see what thier movement patterns are. For the souls release critter ( sry, cant remember the name) force a hero monk to cast [protective spirit] on a warrior and flag it to the critter to absorb the initial (huge) hit.
One group at a time [Cry of Frustration] [cry of pain] is your friend. Run and flag if you mess up or miss stopping a [Meteor Shower] its a long recharge so you can come back and kill them when your party is out of the showers range