Warning: Long post! I've written this to help druids healing 25 man Sartharion+3. Below are all of the things you need to know as the MT healer for this fight, including a video showing where to stand, where to run to, the position of the waves, etc. It's not the full strategy - if you want an excellent overview of the entire fight, I recommend this video which explains the different stages, incoming damage, and all the things that the raid should expect.
Rather than explain the entire fight, I wanted to be specific and cover the things that you will need to do as the MT healer. It's quite a long post but I think that if you are trying to get this fight down, you'll want every advantage possible, so it's worth seeing if there are things you might have missed previously.
A druid as the MT healer
As resto druids, we are fantastic as MT healers for this fight. The MT basically keeps Sartharion occupied while the rest of the raid deals with the messy business of taking out the drakes and various adds. Frightful business, that.
Damage on the MT is normally fairly predictable but can be spiky, particularly when Sartharion casts Flame Breath and takes a chunk of your MT's health off. For most of the time, our complement of HoTs is great (and very economical) for keeping the MT topped up, and for the times when he takes spike damage, Regrowth, Swiftmend and occasionally NS+HT is perfect.
Anyway, the point is, I believe we are best suited to MT healing this fight, so I'm going to share my tips for doing it. I'm not going to cover the entire strat, there are plenty of places that will give you full strategies - I'm just going to share how I MT heal this fight, because that's probably the role you're going to be put into if you're doing this boss.
We usually take 6 healers, and for interest our first kill was two priests, two druids, a shaman and a paladin (although our usual setup tends to be one druid and two shamans). This may seem like stretching the healing quite thin, but it is important to get as much dps in the raid as possible to be able to down the drakes fast enough, so it's best to take as few healers as you can - which is why it's good that there only needs to be one healer on the tank.
A priest (or second druid, depending on your composition) can help by throwing additional HoTs on the MT to be on the safe side and guard against a string of big hits. I am usually okay to heal the MT by myself for the majority of the fight (until the point where the drakes are dead and damage is increased), but don't ever be afraid to speak up and ask for a little help from the rest of your team if you feel the spike damage is a little too much to handle on your own.
Heals & rotation
The "rotation" is really quite straightforward:
1. Keep all of your HoTs on the tank at all times (no brainer).
2. When Sartharion leans back and arches his neck, he's going to cast Flame Breath. Start casting a Regrowth and it should land just after the breath, then either Swiftmend or cast another Regrowth to finish topping the tank back up.
3. When running in and out for lava waves, you may need to use Swiftmend on the run if a Breath comes while you're on the move. I also sometimes use Nourish for a super quick top-up before I run back, but that's up to you and what you prefer to use (I tend to use Nourish in 5 mans and PvP, not very much in raiding). Remember also that it is 100% safe to stand in the lava (it ticks for hardly anything) if you need to stop to heal the MT before running back in - just be careful of voids popping up, as they are hard to spot on top of lava.
4. Finally, if the other tanks wander into your range, toss them a Rejuv to help out. Having "range" showing on your raid frames is essential for this.
That's really it. Keep the MT topped with your HoTs, and use your direct heals to top him off following a breath. The hardest part, really, is watching your frames and timers while you keep an eye out for void zones and lava waves.
Note: IF YOU AGGRO AN ADD - call it out. There's so much going on that a tank may not see you're in trouble. But don't panic - you should be able to keep a HoT on yourself while still healing the tank, so you can effectively tank a couple of adds (not the enraged blazes though) until a tank can come and grab it. Just another cool thing about being a druid - we can offtank while we heal ;)
This is the fun part. You get to stand by yourself, up the front of the raid, away from the mess and chaos! It almost feels unfair to everyone else.
There's a reason for this position though. If you stand with the bulk of the raid, some of the lava wave calls will force you backwards, a few yards out of range of the MT. This will often prove fatal if a breath happens and HoTs are not enough.
So, instead, you stand on Sartharion's back foot and heal the MT from there.
Be careful not to stand too far towards his tail (a stun on you will likely kill your tank) or too far forward. However, it is better to stand more towards his head than his tail, because towards his head you will be cleaved for minor damage (easily healed with a rejuv), whereas a stun is very serious. BE CAREFUL though - standing too far to the right can get you breathed on, which will kill you instantly.
Confusing? You'll see what I mean when you stand there, don't worry. It's quite a small sweet spot and can be hard to judge (I still get the occasional cleave, and last night I was breathed on), but it is definitely better than being out of range of your tank for a few seconds. Standing by yourself also greatly reduces the number of voids you have to deal with, because voids spawn under people, so logically if there is only one person in a big area, it's going to be easier to spot - compared to everyone behind in the mess of players and AoE.
If lava approaches from the right, take a few steps backwards and continue healing. When lava waves come through from the left, you run through Sartharion to the other side (pause to heal if necessary), turn and run back.
Gear & consumables
Really I'm just posting this because I know some people feel better if they have some kind of stats benchmark - people often ask how much spellpower and mp5 they need for particular instances and bosses. I've grabbed a few upgrades since our first kill, but going back to the gear I was wearing at the time, my stats were:
CRIT: 277 (I've since lost 107)
This fight is about execution though, and I think that I could heal this fight in much lower gear and still be fine. It's more about the timing of your heals during spike damage rather than having insane gear, so I wouldn't worry too much if your stats are a bit lower. Your job on MT healing is not terribly gear-dependent.
You definitely don't need massive mana regen in this fight, in fact I often don't need to pot or innervate until the very final stages (at which point other healers can step in to help because the drakes are down). So you should be choosing spellpower over say, mp5 consumables - eg Flask of the Frost Wyrm and spell power food to boost your HoT ticks and direct heals as much as possible.
However, like many fights, you'll probably find you go through your mana quite quickly while learning, because you need to get into the rhythm of the incoming damage and tend to overcompensate with extra casts (I know I do this while I'm trying to settle into a new fight). So you might like to use an mp5 flask at first while everyone is learning, and then switch to spellpower later once you've got a hang of how much healing you need to do.
Cupcakes are recommended but not mandatory.
Final tip: Punch that ankle!
Each week I joke that I'm adding extra dps on the boss, but by turning on auto-attack and punching away at Sartharion's foot, I am actually giving myself extra chances to proc Omen of Clarity (especially during times that I am just refreshing HoTs and not healing heavily), since OoC works on both melee attacks and spellcasts. It's not much, but hey, every little bit helps.
Auto attack will stay switched on even while you are healing, so you can toss a heal and go back to punching him automatically. Of course, this will only work if you use mouseover macros to heal the tank and others - if you have to select a target to heal, you'll stop smacking the boss.
So - slap that dragon! Besides helping to conserve mana, it's highly entertaining.
Finally, here's a short video (sorry it's so quiet) showing you most of the above:
- where to stand
- the approach of each lava wave
- safe spots
- how to recognise incoming spike damage
Hope this helps someone :)