Heres a picture I made when we learnt Felmyst. Since then we're actually changed the positioning again to something cleaner - but this served us well for our first learning attempts:
Red circle = Encapsulate radius
Yellow circle = Mass dispell radius
The main things to note:
- The raid forms a 4 point square around the boss. The middle of the square is the crate in the middle of the field, and the bosses hitbox edge is positioning to be on this square, where the melee stand.
- Three of these points are groups, the other point (top right) is just a single Paladin. The melee are in the middle and only have to move a SMALL amount when a encapsulate hits a range group (maybe 1-2 steps)
- This is a 4 priest setup. 4 priests dispell 4 groups (3 ranged + melee) , and the ProtPally dispells the MT. The Holy Paladin on the top-right single part of the square dispels himself.
- During an encapsulate, adjacent points of the square heal that person. For example, in a setup like
A--B
----
C--D
If 'A' got encapsulated, that group runs off, obviously. All the healers in "B" and "C" heal that person.
Like I said, we've since improved on this positioning to something more comfortable for us, but this was a good initial way to learn the fight. Encapsulate will only hit ~5 people at time. If you run with 8 healers the actual number of healers will look like this, around the squre;
2healer--------1 healer
-------------------------
-------------------------
3 healer-------2 healer
If you notice with this above diagram, no matter which corner of the square gets encapsulated, there will always be FOUR healer on both adjacent points available to heal that person. From there its just a matter of spreading around your Paladins appropriately around the square and ensuring the positioning is setup correctly (all adjacent points within healing range of each other) and that your healers are actually fast enough to keep the encapsulated person alive.
We run with 4 shamans for this boss. We give our MT heroism on every pull. Alternate shamans between fast wipes so that he will always get a heroism upon engage. The fight is long enough that your other shaman will have his CD up ready by 20% for the dps group hes swapped in to.