My team has a pally , priest, 2 locks and a mage (sheeps, water & portals beat the extra lock for me) - combined AoE is pretty awesome.

I set my casters up in a V shape with the mage in the middle at the back, have the pally round up mobs, - I have Minimap ping on the same macro as consecrate so I start with consecrate + 2 x Rain of Fire and a Blizzard.

When the mobs aggro the casters and run into the 'kill zone' inside the V - (switch to concentration aura), 2 x Hellfires with the mage doing Blast Wave , AE spam and a final Cone of Cold - collect loot.