Blood Queen Lana'thel
Positioning and abilities
Positioning in this fight is very important, as large chunks of Lana'thel's raid damage is the result of player proximity to one another. Several raid strategies have ranged DPS and healing spread out as much as possible, ideally with healers closer towards the center of the room but not dead center. This allows the healers to still be in range of the raid while allowing a clear path for later on in the encounter. Your target here is to be at least 6 yards away from any other player; we'll talk about why a little bit later.
The blood queen has several abilities that you need to watch for. When she is engaged, she will cast Blood Mirror on the main tank and another Blood Mirror on the person nearest to the tank, linking them together. The linked player then takes 100% of the damage the tank does as unresistable Shadow damage. When you are engaging her, be careful how you run in to set your totems; if you are too close, it is possible to be the recipient of Blood Mirror. She will also cast Delirious Slash every 20-25 seconds on the player soaking Blood Mirror. This deals 50% weapon damage to that player and leaves them with a 15-second bleed DoT. If you are healing the tanks, make sure to watch for this; the off tank player may take sudden spikes in damage. Riptide works well here on the off tank, as does Chain Heal, which can hit not only both tanks but also give a little spillover healing to the melee. Keep Nature's Swiftness ready just in case the Blood Mirror victim takes a large hit and needs to be topped off quickly. The main tank is a good candidate for Earth Shield, which will give you a little breathing room when you are focusing on the Blood Mirror victim after a particularly nasty hit.
Lana'thel will occasionally cast Pact of the Darkfallen on three random members of the raid. This links the players together with a very bright beam similar to the one that connected the blood princes together. When players are linked, they will constantly explode, dealing shadow damage to one another and any non-linked players who are within 5 yards. In order to remove the debuff, the linked players will have to run to one another and stand right on top of each other for a few moments. This is why most strategies call for the center of the room to remain clear. This allows the players who are linked to move to a central location in order to get rid of the debuff. This also works in a healer's favor, as all three victims will be heading to the same region. Riptide, Chain Heal and hasted Healing Wave can be very useful here to keep these players alive long enough for the debuff to be removed. In the case of Chain Heal, there is also the added benefit of healing any non-linked players who have taken damage from the pact.
Be sure to watch for players who are targeted by her Swarming Shadows. This ability is almost the exact same thing as Lord Jaraxxus' Legion Flame. Most strategies call for players to make a dash for the wall and kite the fire along the length of the wall. Depending on where the targeted player was standing, it is very important to watch out for walls of fire; the targeted player may have had to cut near you to get to a wall. The flames will also deal a constant stream of damage to any player too close to them. If you see yourself taking damage, be sure to quickly scan around you and move away from the the purple fire. Targeted players will be taking damage as well, so be sure to keep an eye on them as they kite, snapping Riptides or nuke heals as necessary.
Lana'thel will also constantly deal damage through Shroud of Sorrow. This will continually pulse, dealing 4,500 shadow damage to everyone in the raid every three seconds. The only thing you can do is heal through it. Shadow resistance will help reduce this damage, and Chain Heal goes a long way to help top the raid off. If your spellpower is high enough and you already have mana recovery from Blessing of Wisdom, you can also use Healing Stream Totem to help give a little additional raid healing to those around you.
Yet another source of damage is Lana'thel's Twilight Bloodbolt. She will target a raid member at random and throw the bolt at them. Not only will it cause damage to the person targeted (roughly 10k damage on 25-man normal mode), but it will also affect anyone standing within 6 yards of one another. This is yet another reason why spreading out is so important here. Again, Chain Heal is great here, not only to heal up the target of the bolt but for any accidental victims who happen to just be standing too close at the time. With the other abilities constantly going on, there may be several times players get accidentally grouped up. Healing Wave is also good for a quick top-off on the bolt victims.
Every two minutes, the queen will run toward the center of the room and fly up into the air. When she flies up, she will do two things. First, she will cast a fear on the entire raid. You should make sure to keep Tremor Totem down for this one. Even though the fear has a short duration, being able to break the fear and move into place quickly helps you start healing again that much sooner and helps those in your group get into position faster to reduce raid damage. After she is in the air, she will cast Bloodbolt Whirl. This is the same as the one she casts on the ground, but here there are multiple bolts and multiple targets. Healing during the air phase is extremely tight, and using Chain Heal with Tidal Force can help you through the phase.
Sounds like a lot of damage to heal through, right? It certainly is, but as the fight progresses and more people become affected by Essence of the Blood Queen, the healing load will lighten. I've also found that using Glyph of Healing Wave has a very good return on investment when it comes to keeping you alive, especially when nuke healing tanks or twilight bolt victims. It will be very handy if you find yourself using the spell a lot to help keep yourself alive.
When to Bloodlust/Heroism
It is widely accepted that the best time for Herolust and other group cooldowns is when the majority of your DPS already has the Essence of the Blood Queen. In 25-man content, this falls shortly after the second Bloodbolt Whirl has completed; in 10-man, this is roughly after the first. This helps ensure that you get the most DPS out of the raid and will hopefully let you take her down before their Frenzied Bloodlust turns into an Uncontrollable Frenzy.
This is actually a very fun fight. There is a ton of raid damage and many things to watch out for. It is a fight where resto shamans really have a chance to shine. Our particular toolset is very useful here, and raid positioning allows us to effectively use some of our best spells and abilities. On a side note, this is also one of those fights where you will really truly appreciate haste; being able to get Chain Heal off that much faster really can make a big difference.
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