Five seconds into the fight two 'a tempest mage' spawn on both stair landings. They are casting a spell and you must find a way to break their concentration. To do so have a player walk up the stairs and into the npc, they will become active and their concentration broken. Make sure the player starts at the bottom of the stairs, the npc can bug if a player is standing on the landing when the mage spawns. Pull them to Zzalazziz and AoE them down as best you can and switch to them if they begin to overwhelm your tank. The pair of mages spawn every 30 seconds.
Burn Zzalazziz completly down and the doppelganger will die. There is balancing of health nor do they have to be close in health. One tank on the doppelganger just holding it and three groups burning the main name until it's dead.
This fight is a combination of high dps and good survivability. With 7 million dps it was still a 10 minute fight and surviving two hard hitting AoEs will be rough on any group without wards. But all and all it is a fairly simple strat once you get use to it.
The new NPC-lookup tool at Soresha.net, pulling from EQ2's census feed, has some exact numbers for ZZalazziz:
Class: Sorcerer
Max Health: 1,448,098,920
Max Power: 13,163,920
Here is a trick. Do not concern yourself with the adds. A raid with 10 million dps turns this fight into 5 minutes or less. Just make sure you trigger the mages RIGHT away and place the mages right on the named. AOE DPS down the mages as you burn Zallizizz down primarily. The mages do very little dps overall if you trigger them right away from their platforms.
Thats actually why we stopped working on it for now. The damage output is insane.
Tanks are still getting whacked with some hardcore damage some guilds are reporting. Upwards of 20k hps from each healer in the tank groups.
The mage AoEs can't be interrupted but shouldn't be too much of an issue as long as your raiders have stifle immunity.
I'd say how far apart you have the names is a matter of preference for your raid. The Static Tempest AoE doesn't seem to have a range restriction and for me being a fury I did not find I was getting hit with less damage being 50 meters or 1 meter from the mob. We do pull the mobs about 50 meters apart (oppisite cornors of the deck) as a precaution so that a tank doesn't AoE aggro the wrong mob and to reduce the chance of frontal AoE damage.