For felmyst, there is no 1 spell that works the entire fight. For P1. I like to wait a little bit untill the raid damage starts to hit then toss out as many lifeblooms as I can before the Gas Nova hits. At that point, I can count on a lot of chain heals to catch most people up so I quickly scan the raid for anyone that wasn't topped off before the Nova. These people need a quick immediate heal so I get them with Max Regrow. I usually spam 4 or 5 of these, hit the tank with a couple hots and watch the dragon to see which way he's going to turn on Encap. For encap, either run away rejuv/sming myself, or stand in place and target anyone else running from encap.
In p2, as we are all running around crazily avoiding the beams, this is my turn to shine. I spam the raid (priests first) with rejuves and Swiftmend anyone that is in dire need of a heal. As soon as the second beam hits and is officially not on me, I once again find a good spot near the paladin and spam regrowth, keeping a full set of hots on the Paly tank as well.
I'm usually near the top of the meters on this one, assuming I don't die stupidly. Here is a link of the most recent Fellmyst kill parse.
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