Disclaimer: This guide is written from the perspective of playing an echo build, as i personally believe it has many advantages over blossom on this fight, however both builds should work fine with different strengths and weaknesses.

Phase One: The Dream Render

Before you even start pulling the boss there is a couple of very important things that are recommended to have ready before hand. The first of these are how do you plan to spread your cooldowns across phase one as this is by far the part of the fight in which you will have more wipes due to lack of healing.

The main damage mechanics of phase one are 426368 and 425481. 426368 will happen at 0:28 and 1:29, while 425481 hits at 0:55 and 1:56.

This means that during the first two minutes of the fight you have four big damage events that you can cover, and you get two stasis, one df, one rewind and one ec. ec and df are really good at handling 425481 as the damage is spread over aproximately 10 seconds, and stasis and rewind are better at dealing at the instant spike of damage from 426368

It's really important that you coordinate with your co-healers in order to spread the cooldowns across the phase as best as possible, but in a worse case scenario you can have something up for every big event as long as you execute properly, even tho this means that you will have to do an ec ramp without stasis and then use stasis on its own to heal the raid in a separate event.

On an blossom build you won't have stasis nor will you be able to ramp lb for ec. Your sustained healing over the phase might be better but your cooldown coverage is much worse

The first phase of the fight is a coordinated dance around the room as your raid strategically drops the fire in specific spots in order to have enough room to dps the boss down to 70% so you can move into phase two. If the fire touches the roots at the back of the room you wipe instantly, and trying to stack the circles will just make the fire spread on its own

Once you have your cooldowns set up properly the difficulty of the fight is executing properly while dodging 421829 lines and the 425345 frontals from the 428954 and, the most stressfull part of it, using nat on cooldown to dispell 417807. There is a lot of avoidable damage in this part of the fight and it's not always easy to evade all of it while keeping up with using all your buttons so be prepared for a lot of wipes here. Don't be afraid to change your cooldown timings if you feel like you aren't getting good value out of them or you are just sniping the other healers.

Intermission

The intermission is very simple but it's also very easy to wipe here. The only difference from heroic to mythic is the fact that the raid will be spread between red and purple debuffs called 429903 and 423972. People can only soak orbs of the same color as the debuff they were assigned.

There are weakauras that can help organize and spread the group across the room to soak all the orbs, and the most common strategy involves using several inmunities to grab all the orbs from the 3rd set and any sane raid leader will let you position near the center so you are decently in range of most of the raid. If you didn't use your second stasis at the end of phase one you will have it up here, and it's a very good place to use it as the raid will be taking heavy damage

Phase Two: Children of the Stars

The gimmick of phase two is the waves of friendly adds that constantly spawn and move across the room, the change from heroic to mythic is a second type of add that spawns along side the night elf ghosts. The Ancient is a single target that requires 5 million healing in order to reach full hp, and at some point in the fight three of them spawn together

The interesting part about this is that in an ideal comp of Mistweaver, Paladin, Discipline Priest and Preservation you are the best choice to focus on solely healing the raid while the others do the job of focusing on the adds. And so you don't really have to do anything different or special to deal with the mechanic besides being ready to pick up the extra healing needed to keep the raid alive while everyone else does.

In case you do need to contribue healing on the spirits, ta, sb, db and ouro are all good choices to do some healing to them, while a blossom build might be best suited for the job as it can just spam blossoms on them non stop

However Preservation is really not good when it comes to doing single target healing to the ancient. What we can do in that scenario really doesn't come close to what a Mistweaver can do, and in any case a holy Priest can do the job way easier than us. We don't have the tools to do constant single target and won't be able to apropiately deal with the ancients. You are better off keeping the raid alive and letting a healer with a more single-target oriented kit do this part of the phase

What we can do to assist the raid with healing Amirdrassil during phase two, is using rescue on the friendly adds to get them closer to the heart, and make them heal the tree ahead of time. With the latest set of nerfs this isn't required to kill the boss but having several adds die early on in the phase might mean that the heart doesn't have enough health and outright dies before the next wave of adds can reach it, even if that would have been enough to keep going.

Keeping an eye out for the health percentage of the tree, and rescueing adds near it when you notice there won't be enough time for them to walk normally can turn a phase two wipe into a smooth transition into phase three

Phase two itself doesn't have a lot of damage hitting on the raid to account for the healers having to pay extra atention to all the adds, the only big hits the raid will take come from 419123 the two times Fyrakk comes down. These happen right at the start of phase two and two more times 1:10 and 1:15 after the last 419123. Any other heavy damage the raid might take would come from 430051, which shouldn't happen if the hostile adds are being properly dealt with

Phase Three: Shadowflame Incarnate

After the recent set of nerfs the final phase of the fight goes by relatively quickly and there is not much damage on it. The hardest part for a guild progresing on it currently would be the danger of constant wipes from any kind of damage touching a 423601. As a mid-range healer you are not and should not be considered for seed carrying, which means you don't really need to pay atention to this mechanic besides knowing where to stand so you don't endanger the seed carries with your 421829.

The big damage events from this phase come from 422837, which should happen at most three times. 423717ing a 423601 will cover most of the damage from the hit itself but it will still considerably damage the raid and leave a hard hitting dot on everyone. Healer cooldowns should be asigned to cover every single 422837 and whatever cooldowns are left can be sprinkled in across the phase as needed to help heal up 421829 damage

Ideally, you should keep extra atention on the people carrying the 430048s, as they will be taking extra damage over the phase, however these players will usually be at the oposite side of the room, and going near them to get in range at the wrong time risks you being targeted by a 421829 or a 425530 and putting them in extra unnecesary danger. The safest course of action is to just keep covering the raid and letting higher range healers spot heal these players

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