I had a group made up of:
- Priest (me)
- Warrior (tanking)
So we didn't have any fire resist auras. I imagine as a Paladin, Shaman this would be easier due to Resistance Aura / Elemental Resist Totem giving 195 resist. (25% damage reduction)
Since I had a group with zero fire resist ability, it seems practically impossible for me to survive without taking deliberate measures such as:
0) Stay at 100% health during the mace phase.
1) Keep one or more of the following spells active on myself at all times during the mace phase: Shield, PoM, Renew.
2) Respec Inner Sanctum 3/3 (reduce spell damage by 6% when Inner Fire is active)
3) Bring a Prismatic Elixir (damage reduced by 13.4%)
4) Replace someone with a Paladin, Shaman or Druid for more fire resist / secondary healing.
5) Put a Lightwell down, click it when I get Impaled.
6) Respec Discipline, use a glyphed Pain Suppresion.
0) Seems to be compulsory.
1) Probably will keep a Shield on myself at all times in this phase from now on. Combined with some other strategies this will make a difference.
2) Definitely a great idea - Veiled Shadows hasn't been that game changing.
3) A good idea. On my server these are cheap right now. You could get one for each person, however this has the potential to become expensive fast if you're not confident of a kill on the next attempt. If you're only buying them for yourself it's worth definitely worth it if you have no other significant mitigation. Keep a stack handy.
4) Not always possible. Besides, this isn't relevant considering they could replace me instead.
5) Lightwell is usable when stunned. I haven't yet tried it in this specific scenario. Might be out of range considering the tank has to kite the boss during the relevant phase. Everyone else in the group can do this too, since they're not doing anything else anyway.
6) Unreliable; you might need it to keep someone else alive, or you might get impaled twice. You have to be able to survive this without relying on cooldowns. (Not even sure if this is a stun, let me know if it isn't.)
I plan to do #0, #2 and #5. If there are no shamans or paladins in the group, I'll also do #3.
Also I will probably have to drink a Ghost Elixir, and bring some mana potions, since I have been struggling with the shield phase AoE damage.
TL;DR: QQ Paladins, Shamans (and to a lesser degree, Druids) can mitigate multiple types of spell damage, priests can only mitigate shadow.
If anyone has advice for mitigating damage on this fight I would be grateful to hear it.