This page covers a healer-focused strategy for Gul'dan in The Nighthold. While it's tailored for healers, other roles may also find the information useful. If you have any suggestions or feedback, you can leave a comment below or tweet @PrestonDvorak.

This guide has been updated and maintained based on my own experiences with the fight as well as Dungeon Journal information. I'll continue to update it as-needed.

General Mechanics and Abilities

Normal and Heroic

Gul'dan is a three stage fight where Gul'dan gets progressively powerful over each stage.

Stage One - lieutenant adds

During this Stage, Gul'dan is hidden inside the Eye of Aman'thul and you fight his Lieutenants instead.

• The Essence of Aman'Thul provides several beneficial effects during this Stage in then form of an Extra Action Button.
• Time Dilation benefits DPS specs by granting increased haste, movement speed, etc.
• Scattering Field benefits healers by placing shield domes at their location when used.
• Resonant Barrier benefits tanks, making them immune to damage for 6-seconds.
• Gul'dan uses several abilities while hidden.
• Move far away from the impact location of Liquid Hellfire to reduce damage taken, or stand inside a Scattering Field placed by healers.
• Avoid the Fel Efflux beam.
• Avoid the impact location of Hand of Gul'dan. This ability is what summons Lieutenants.
• Fel Lord Kuraz'mal
• Uses Time Dilation to hit the tank for massive damage. This will require a Resonant Barrier or substantial cooldowns to survive.
• On Heroic, avoid the Fel Obelisks, which will impale and stun players hit when they appear.
• Inquisitor Vethriz
• Summons Gaze of Vethriz adds at random locations. Avoid their channeled eye-beam.
• Dark Blast deals damage to random targets.
• Uses Shadowblink to move randomly around the room.
• On Heroic, Drain must be dispelled quickly from players to avoid Inquisitor Vethriz being healed.
• D'zorykx the Trapper
• Run against the pull of Soul Vortex. Each subsequent cast gets harder to run against, be ready with movement speed buffs.
• On Heroic, avoid Anguished Spirits when cast, if possible.

Stage Two - gul'dan

With his lieutenants defeated, Gul'dan joins the fight. At 85%, 70%, and 55% health he will empower his abilities, as noted below.

• Beneficial effects from Essence of Aman'thul continue in this Stage.
• Continue to run away from, or be shielded from, the impact location of Liquid Hellfire.
• At 85% health, this changes to Empowered Liquid Hellfire.
• Avoid the patch of fire left behind after the blast.
• When affected by Bonds of Fel, slowly run away from the location you're bound to. Other players will need to stand at your location before you break it in order to evenly divide the damage dealt when the bonds are broken.
• At 70% health, this changes to Empowered Bonds of Fel. 
• When affected by the bonds, you're now knocked back initially and suffer a 70% movement decrease, up from a 50% decrease.
• Stand near the center of the room before this is cast to avoid being knocked off the platform.
• Eye of Gul'dan summons Eye of Gul'dan adds that channel steadily increasing damage at random players, also dealing damage to anyone within 8-yards of the targeted player.
• At full energy, Eyes of Gul'dan use Duplicate, creating a new Eye at a new location.
• At 55% health, this becomes Empowered Eye of Gul'dan.
• Empowered Eye of Gul'dan adds channel even higher increasing damage at random players.
• Don't stand in front of Gul'dan to avoid Fel Scythe.
• Tanks must manage Fel Scythe in such a way as to keep the damage it deals at a manageable level without allowing Fury of the Fel to stack too high.
• On Heroic, continue to avoid the impact location of Hand of Gul'dan.
• This now summons a Dreadlord.
• Carrion Wave should be interrupted.
• When interrupted, the Dreadlord's Focused Assault grants a stack of Fervor.

Stage Three - buffed gul'dan

At 40% health, Gul'dan harnesses the full power from the Essence of Aman'thul.

• Beneficial effects from the Essence of Aman'thul are no longer available in this Stage.
• Empowered Eye of Gul'dan continues to be used.
• Fel Scythe also continues to be used.
• Move out of the sequentially expanding rings created by Storm of the Destroyer. The first ring is 10-yards in diameter, then 20-yards, and finally 30-yards.
• Well of Souls creates a Well of Souls in the center of the room, which Gul'dan periodically adds souls to.
• Players affected by Soul Siphon gain a healing absorption debuff and have their soul added to the Well of Souls.
• Standing inside the Well of Souls for 3-seconds will free a soul and inflict damage to all players within 5-yards and apply the Soul Corrosion debuff.
• Soul Corrosion can stack multiple times and lasts up to 3-minuntes. For example, if you stand inside the Well of Souls for 6-seconds you will free two souls and gain two stacks of Soul Corrosion.
• Managing the number of souls inside the Well is important as it will reduce the damage done by Black Harvest.
• When affected by Flames of Sargeras, move away from other players and move out of the explosions and Desolate Ground left behind.

Mythic Differences

On Mythic, the fight essentially starts in Stage Two from Heroic, with Gul'dan already in the fight.

Stage One - gul'dan

• All of Gul'dan's abilities are already empowered by the Essence of Aman'thul.
• Eye of Gul'dan summons Lieutenants, instead of Dreadlords.

Stage Two - buffed gul'dan

• This Stage functions the same as Stage Three on Heroic, when Gul'dan reaches 50% health he becomes fully empowered, and players no longer have access to the Essence of Aman'thul's benefits.
• Storm of the Destroyer now expands a fourth time, up to 60-yards.

Healing Strategy

This fight has a lot going on, but the healing needed is predictable.

Stage One - lieutenants

• Liquid Hellfire deals light to moderate damage to the entire group.
• Soul Vortex deals light damage to the entire group when D'zorykx the Trapper is active.
• On Heroic, Anguished Spirits will deal critical damage to anyone hit when D'zorykx the Trapper is active.
• On Heroic, Drain must be dispelled quickly when Inquisitor Vethriz is active.

Stage Two - gul'dan

• Liquid Hellfire continues in this Stage.
• Players affected by and soaking Bonds of Fel will need moderate healing.
• Carrion Wave deals moderate damage to players in front of Dreadlords if not interrupted.
• On Mythic, this is essentially the Stage the fight begins in.

Stage Three - buffed gul'dan

• Players afffected by Soul Siphon will need moderate healing to remove the absorb effect.
• Players with Soul Corrosion will also need increasing healing as they gain more stacks.
• Players affected by Flames of Sargeras will need light healing while the damage over time effect is active.

 Debuffs to Track

• Drain must be dispelled.
• Several abilities cause players to need additional healing.
• Soul Siphon
• Soul Corrosion
• Flames of Sargeras

 DBM Settings

Below are the DBM settings I'll be using for Gul'dan. You can set them up however you'd like, but these ones should work well as a starting point. Some settings may be Mythic only.

Healer DBM settings for Gul'dan

 Videos

Heroic, Restoration Druid PoV

Below is a video of me and my guild defeating Elisande on Heroic difficulty. There is no commentary, only game sounds.

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