Valithria Dreamwalker is a green dragon. During WotLK, she was captured by the Scourge and held prisoner. She is the first boss of the Frostwing Halls wing of the Icecrown Citadel raid. The fight ends when the raid has succeeded in healing Valithria up to 100%, while adds spawn in decreasing intervals.
During the war against the Lich King, Valithria was captured by the Scourge and placed within Frostwing Halls wing of the Icecrown Citadel. The Scourge was using her as a test subject for their own ends. Heavily wounded, the Lich King ordered the Scourge to hasten her destruction and to leave only bones and sinew for her reanimation. However, Azeroth's champions were able to successfully beat back the Scourge and heal her wounds.
After she was restored to her powerful self, she changed to the form of a high elf and explained a few things about Sindragosa to the adventurers.[1]
The fight is a chaotic battle for survival. The loss of a tank or a healer could easily result in a wipe.
This boss is available since February 2, 2010 on US servers and February 3 on EU servers.
As of patch 6.0.2, the door behind Valithria is now open by default. Previously, a non-healing class could not complete this encounter and thus was unable to progress any further in the raid.
In the Frostwing Halls players will battle alongside the Ashen Verdict and push into the lair of the deadly frost wyrm Sindragosa, who continues to strengthen her brood with the help of Ymirheim's vrykul. Along the way, the heroes will stumble upon Valithria Dreamwalker, a captured green dragon whom the Scourge is using as a test subject for their own ends....
Nightmare Portal — Summons a Nightmare Portal to allow players access to the Dreamstate, where Dream Clouds spawn. (8 portals each time on 25-man)
Emerald Vigor 50,000 yd range — Regenerating 200 Mana every 3 sec. Increases Damage done by 10%. Increases Healing done by 10%. Instant. 10 yd radius. 35 sec duration. Stacks to 100. Cast when a Dream Cloud is killed in Valithria's dream state.
Dreamwalker's Rage — Deals 10,000,000 Nature damage to all surrounding enemies. 3 sec cast. 50,000 yd radius. Cast after reaching full health. Will not hit players.
Fireball — Inflicts 4,713 to 5,287 Fire damage to an enemy.
Lay Waste — Surrounds the caster in flames for 12 sec, pulsing 3770 to 4230 Fire damage to all enemies every 2 sec. Instant. 50,000 yd radius. 4713-5287 on Heroic
Acid Burst — The caster explodes, dealing 9425 to 10575 Nature damage instantly and 750 Nature damage per second to all enemies within 15 yards. Lasts 20 sec. 11782-13218+900/sec on Heroic
Corrosion — Whenever the caster lands a melee swing, the target takes 2000 Nature damage every 3 seconds and their armor is reduced by 10%. This effect can stack up to 5 times. Lasts 6 sec. 2500/3 on Heroic.
Column of Frost — Marks the location under a random player target. After 2 seconds a column of frost erupts from this location, dealing 11310 to 12690 Frost damage to all enemies within 3 yards, knocking them into the air. Instant. 3 yd radius. 14138-15862 on Heroic.
Frostbolt Volley — Inflicts 8550 to 10450 Frost damage to nearby enemies, reducing their movement speed for 4 sec. 1.5 sec cast. 200 yard radius. 10800-13200 on Heroic (8 sec cooldown) (This can be interrupted, as well as dispelled.)
Mana Void — Summons a Mana Void at a random enemies location. This Mana Void burns 800 mana per second to all enemies within a 6 yard radius. Lasts 30 seconds. Instant. 1000 mana on Heroic
Gut Spray 8 yd range — Deals 2000 Nature damage per second and increases Physical damage taken by 25% for 12 sec. Instant. Disease. 9425-10575 Nature damage initial blast; 11782-13218+2500/sec on Heroic. This is a removable disease.
Spawn Rot Worms — Spawns 8 to 10 Rot Worms after the abomination dies.
Suppression (Channeled) 50,000 yd range — Reduces healing received by the target by 10%. Lasts until cancelled. Cast on Valithria.
Setup
Valithria starts at 50% health and the objective is to heal her up to full. Between half and two-thirds of the healers should concentrate on her, while the other healers keep the raid up. This usually translates to 1 Raid healer and 1-2 healers on Valithria (10 Man) or 2 raid healers and 3-4 healers on Valithria (25 Man).
Adds spawn from the gates. In 25 player, all four gates spawn adds, in 10 player it's only the front two. The spawn rate increases over time. After 7/? (10/25 player) minutes, Suppressors and Blazing Skeletons start to spawn continuously, which usually leads to a quick wipe.
A basic strategy is to loosely assign one group of tanks and damage dealers per add portal.
Positioning
10 Player
Since only the closest two gates spawn adds, the back half of the room can be ignored (except when dream portals are opened). One or two damage dealers should be assigned to deal with suppressors. Suppressors can spawn from either side or both at once and only have about 35,000 or so health. The tanks should stand in the middle between the two gates to handle any Archmage or Abomination that comes out. Valithria's healers should set up near her, but close enough so that the tanks can still see them in the event that something needs to be pulled off of them.
25 Player
The raid should split up into two groups, one positioned to the right of Valithria, the other to the left. Each group is responsible for the adds that spawn on their side, and should only take care of adds on the other side if all adds are dead on their side or they migrate over. Healers assigned to Valithria should stand in the middle of the room "within" Valithria, and only move to jump into portals. This forces the adds to move through the kill groups on either side of her and reduces the chance of migration and missed adds killing the healers. Follow the same kill priorities, and techniques as for 10 player.
Add portal groups
The add portal groups should use the following priority list:
One raid member per portal focuses on Suppressors (Cat druids are quite effective).
Everyone else kills Blazing Skeletons first.
Zombies are kited by a predesignated ranged DPS.
Archmages get tanked and taken out by melee.
Abominations get tanked and taken out by ranged DPS.
Class-specific tips
Feral druids are particularly effective against the Suppressors with [Swipe].
Paladins are good for tanking the Abominations, as [Consecration] helps to gather up the worms that spawn, allowing casters to quickly AoE them down.
Death knights are good for tanking the Archmages as Frostbolt Volley can be interrupted.
Mages can use Blizzard to kite and help kill the rot worms.
Hunters are useful against the Zombies, as they can use [Distracting Shot] to make sure the zombie initially heads to the hunter and then gain aggro normally through regular attacks as well as use [Ice Trap] and [Concussive Shot] to slow them down. Mages can use Frostbolt to kite the Zombies.
Any class that has a heal should heal Valithria whenever there is a break in the action for them. Every little bit helps. Even bandaging helps. Also, these classes should patch themselves up whenever possible to reduce the strain on the healers.
Dream Portals
Every 30 seconds, Valithria provides portals to the Dream. These portals initially appear as small green orbs on the floor even before they can be entered. The Valithria healers should move close to these orbs and enter the portals as soon as they appear. Only one person can use each portal.
The Dream is a version of the room where only Valithria, several green orbs, and the players who entered exist. The objective is to float through as many green orbs as possible. When a player touches an orb it explodes (no damage) and provides a stacking buff (Emerald Vigor), which increases mana regeneration and healing done. After a few seconds, the players automatically return from the Dream and rejoin the rest of the raid. Now they spam heal Valithria until the next portals spawn. As the portals spawn every 30 seconds, and Emerald Vigor's timer is 35 sec, it should never run out and stack sizes should gradually increase up to over 30 near the end of the fight.
Since Emerald Vigor also increases damage done, it may be possible to have DPS classes enter the portals. Preferably this should be a class with low ramp-up time, namely Warriors, Combat Rogues, Hunters, Shaman or any other class/spec that takes a short amount of time to do a large amount of damage.
The Dream can also be used to avoid getting killed before a wipe. With good timing and a little luck, it's possible to enter the dream and drop out only after combat has finished. After the end of combat there are a few short seconds to run out of the area before respawn.
If players stand in a Frostbolt Volley from an Archmage, they are slowed even while in the Dream. For this reason it's important to interrupt Frostbolt Volleys. Paladin and priest healers can quickly cleanse themselves, druid healers can shapeshift out of the effect - so make extra certain to interrupt if a shaman is going in.
Strategy
Once the groups are all positioned properly, begin the fight by pulling the four Risen Archmages that are present in the room at start. They stand in a square shape around the boss on 25 player, or in a semi-circular shape between the boss and the raid on 10 player. These mobs should die quickly.
The healers assigned to Valithria should take a portal when they spawn, and aim to collect as many stacks as possible each time. DPS classes shouldn't need to take the portals, however having a couple of good DPS building stacks can make life easier later on when the adds start spawning a lot faster.
Near the end of the fight, when Valithria's health is already high, use Bloodlust/Heroism and don't enter the portals again. The proper moment for this has to be found out by experience. Assume a raid normally uses Bloodlust after the 6th portal phase and then wins after the 8th. That same raid would defeat her faster when they would use Bloodlust after the 7th portal phase, and not enter the 8th portals.
Heroic Mode
Although semantically very different, the actual encounter has only a few differences on Heroic mode.
The Frostbolt Volley cast by the Risen Archmage now burns 2000 mana, meaning that interruptions become crucial to stop more mana-intensive classes from running out of mana.
Valithria's health decays over time. While she still starts at half health and remains at the same max health as normal mode, the decay means more healing is needed as the encounter goes on.
Blistering Zombies run much faster than normal.
Instead of opening portals into the Dream, portals instead open into the Nightmare.
Valithria does not announce these portals opening.
Players take damage while inside the Nightmare, and the orbs also apply a DoT in addition to their usual effects.
The Lich King yells: Intruders have breached the inner sanctum! Hasten the destruction of the green dragon, leave only bones and sinew for the reanimation!
Valithria Dreamwalker yells: Heroes, lend me your aid! I... I cannot hold them off much longer! You must heal my wounds!
Opens portal
I have opened a portal into the Dream. Your salvation lies within, heroes...
75% Health
My strength is returning! Press on, heroes!
25% Health
I will not last much longer!
Victory
I AM RENEWED! Ysera grants me the favor to lay these foul creatures to rest!
Unused quotes
Forgive me for what I do! I... cannot... stop... ONLY NIGHTMARES REMAIN!
Valithria Dreamwalker
[50] In Darkness, I Dream questline.
Blizzard Entertainment
Nightmare Portal — Summons a Nightmare Portal to allow players access to the Dreamstate, where Dream Clouds spawn. (8 portals each time on 25-man)
Emerald Vigor 50,000 yd range — Regenerating 200 Mana every 3 sec. Increases Damage done by 10%. Increases Healing done by 10%. Instant. 10 yd radius. 35 sec duration. Stacks to 100. Cast when a Dream Cloud is killed in Valithria's dream state.
Dreamwalker's Rage — Deals 10,000,000 Nature damage to all surrounding enemies. 3 sec cast. 50,000 yd radius. Cast after reaching full health. Will not hit players.
Fireball — Inflicts 4,713 to 5,287 Fire damage to an enemy.
Lay Waste — Surrounds the caster in flames for 12 sec, pulsing 3770 to 4230 Fire damage to all enemies every 2 sec. Instant. 50,000 yd radius. 4713-5287 on Heroic
Acid Burst — The caster explodes, dealing 9425 to 10575 Nature damage instantly and 750 Nature damage per second to all enemies within 15 yards. Lasts 20 sec. 11782-13218+900/sec on Heroic
Corrosion — Whenever the caster lands a melee swing, the target takes 2000 Nature damage every 3 seconds and their armor is reduced by 10%. This effect can stack up to 5 times. Lasts 6 sec. 2500/3 on Heroic.
Column of Frost — Marks the location under a random player target. After 2 seconds a column of frost erupts from this location, dealing 11310 to 12690 Frost damage to all enemies within 3 yards, knocking them into the air. Instant. 3 yd radius. 14138-15862 on Heroic.
Frostbolt Volley — Inflicts 8550 to 10450 Frost damage to nearby enemies, reducing their movement speed for 4 sec. 1.5 sec cast. 200 yard radius. 10800-13200 on Heroic (8 sec cooldown) (This can be interrupted, as well as dispelled.)
Mana Void — Summons a Mana Void at a random enemies location. This Mana Void burns 800 mana per second to all enemies within a 6 yard radius. Lasts 30 seconds. Instant. 1000 mana on Heroic
Gut Spray 8 yd range — Deals 2000 Nature damage per second and increases Physical damage taken by 25% for 12 sec. Instant. Disease. 9425-10575 Nature damage initial blast; 11782-13218+2500/sec on Heroic. This is a removable disease.
Spawn Rot Worms — Spawns 8 to 10 Rot Worms after the abomination dies.
Suppression (Channeled) 50,000 yd range — Reduces healing received by the target by 10%. Lasts until cancelled. Cast on Valithria.
[Swipe].
[Consecration] helps to gather up the worms that spawn, allowing casters to quickly AoE them down.
[Distracting Shot] to make sure the zombie initially heads to the hunter and then gain aggro normally through regular attacks as well as use 
[Ice Trap] and 
[Concussive Shot] to slow them down. Mages can use Frostbolt to kite the Zombies.
[Portal Jockey (10 player)]
[The Frostwing Halls (10 player)] (
Heroic)
