Just a quick note regarding the Gluttonous Miasma: Although targets with it are immune to healing, they can still receive shields - so feel free to spam shields on these players to help them survive some of the more nasty moments. - Alex
If you have to drop a ball and you have miasma you need to burn a defensive CD to survive. If you get it again before your CD resets, you just die. This fight is ridiculous because we are a small raid group and we just wipe when people die to getting bad RNG.
As always Fatboss gives a great guide, however it's missing what should tanks do if they get the Miasma debuff, my guild attempted this last night and several times both tanks got the debuff at the same time.