Haven't got to finish this one but i think i understand how it's supposed to be done.
1x boss (lord) + 2x brides
Left bride has a golden aura (big bubble effect like deflect oil) - golden aura is added dmg
Right bride has a black aura - black aura is added dmg
takenMain tank needs to tank boss in the middle and the two brides need to be tanked in each side.
Boss won't take more than 1 dmg per hit unless the person who tanks the black aura bride moves so that the boss is inside the black aura -> Only the person tanking the black aura bride and the boss should be in the black aura.
The golden aura bride is being tanked at the left side - All the dps:es and preferably the main tank should be inside the golden aura to get the boss killed as fast as possible.
If you kill a bride the boss will enrage.
After about 6 minutes the boss will enrage.
This is what i've gathered so far, feel free to update ^^