A good write up on what is arguably one of the hardest fights for a healer in this level of content. I figured I'd add my view on the heroic 25 version, I have been finding myself ignoring the raid to solo-heal the tanks and assigning the other healers to deal with the raid - but our other 2 paladins are finding that WoG use is powerful for this fight (admittedly it seems this is the only fight) and Flash use is quite heavy in order to do the raid healing. On heroic he does not stop attacking during feud (pretty much the main difference other than in the last phase there is an aoe damage aura that slowly kills your raid and he has more hp obviously) and light of dawn is relegated to feud raid healing. During feud however, you can (and I recommend you should) "cheat it" by popping a raid -damage CD, either from a prot or a discipline priest. It makes the healing near trivial even on heroic, and if necessary the use of the baradin hold resistance use trinket is excellent for negating the damage (which is also amazing for nefarian).

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