Instance: Hall of Lightning (normal)
Box: Protecting Warrior, Arcane Mage, Survival Hunter, Elemental Shaman, Restoration Druid
Gear level: lvl 80 Warrior in mostly epic gear, lvl 80 shaman with some epics, lvl 78 hunter/druid/mage with mostly blues
Difficulty: Easy once I figured out the tactics
Guide:

General Bjarngrim / Ionar
Check here for tactics.

Volkhan
Ignoring the additional spawned mobs made the fight a lot easier. Just like on heroic.
I put down a fire resistance totem, but I'm not sure if it helps.

Loken
Position with /follow like this: [dps+healer] -> [tank] -> [boss]

Sequence:
1) Run to the boss and align so all your characters (including the tank) face in the same direction. Make sure you can either strafe left OR right far enough to be able to avoid Lightning Nova.
2) When Lightning Nova is being cast by the boss, make sure that your strafe keys are broadcast to all characters and start strafing away from the boss.
3) After Lightning Nova, remove strafe broadcasting, press your /follow macro key and repeat from 1)

About healing:
The most important is AoE healing: druid AoE HoT + shaman healing stream totem kept the healing of the part members at 100% almost all the time.
The tank needed a little extra healing sometimes.