Cathedral of Eternal Night, Healer Guide

Patch 7.3 Updated
September 05, 2017

This page covers healer-focused strategies for the bosses in the Cathedral of Eternal Night dungeon. 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 fights as well as Dungeon Journal information. I'll continue to update it as-needed.

There is a summary of debuffs to track at the very bottom of the page.

[LGN] 7.2 PTR, Heroic Cathedral of Eternal Night, Guardian Druid PoV (Game Sounds Only)

Agronox Dungeon Journal ModelAgronox

During this fight, you will face Agronox and several types of floral adds.

  • Poisonous Spores deals steadily increasing damage to the group.
  • Don't stand in front of the boss to avoid Timber Smash.
  • When affected by Choking Vines, run away from the source to break the vines.
  • If fixated by a Fulminating Lasher, run away from it. Getting caught triggers Floral Fulmination.
  • Avoid the Toxic Sap puddles left behind when Succulent Lashers are killed.
  • On Mythic, Nourishing Lasher need to be killed quickly to mitigate the healing done by Nature's Infusion.

Healer DBM settings for Agronox

Thrashbite the Scornful Dungeon Journal ModelThrashbite the Scornful

During this fight, you will face Thrashbite and magical books inside a circular library, with the bookshelves playing an important role in the fight.

  • The very center of the room is the safest place during this fight, as it helps you avoid several mechanics more easily. The boss should be tanked in the center of the room.
  • When Pulverizing Cudgel is used, run out of the circle around the boss.
  • When Scornful Gaze is used, several things need to happen.
    • If you're the target of Scornful Gaze, run behind one of the bookshelves to avoid the damage from Scornful Charge.
    • If you're not the target, avoid being in the path of the charge, which is denoted by a red line between the boss and the affected player.
    • After the charge, don't be in the path of the boss as he runs back to the tank to avoid damage from Wild Thrash.
  • Immediately after, move to the center of the room to avoid Destructive Rampage. The damage area extends slightly beyond the bookshelves, making the circle in the middle the safest place.
  • On Mythic, several different book adds will join the fight.
    • All books use Arcane Bolt on their current aggro target.
    • Satirical Animated Book
    • Fictional Animated Book
    • Biographical Animated Book
      • Beguiling Biography charms a random player. This player must be damaged down to 30% health to break the effect.

Healer DBM settings for Thrashbite the Scornful


Domatrax Dungeon Journal ModelDomatrax

This is a multi-stage fight during which you fight Domatrax and several types of demon adds while using the Aegis of Aggramar to protect yourself against certain attacks.

  • The Aegis of Aggramar creates a circular shield in the center of the room that gets smaller as it absorbs damage from various attacks, explained below, until it eventually disappears.
  • Domatrax uses the following abilities during all stages of the fight.
    • Don't stand in front of the boss to avoid Felsoul Cleave. This should also be pointed away from the Aegis of Aggramar to avoid draining it unnecessarily.
    • When Chaotic Energy is used, stand inside the Aegis of Aggramar to mitigate the damage.
  • Fel Portal Guardians periodically spawn around the edges of the room, and must be killed quickly.
    • On Mythic, these channel Approaching Doom.
      • If this channel finishes, a Searing Overfiend emerges from the portal and afflicts the entire group with Searing Presence.

Stage 1 - the march of the felguard

  • At 90% health, Domatrax opens two portals allowing Hellblaze Felguards to enter the fight.
    • Avoid standing in front of these adds and avoid the puddles left behind by Searing Rend.

Stage 2 - the burning hordes

  • At 66% health, three portals are opened allowing Felblaze Feasters and Felblaze Imps to enter the fight.
    • Felblaze Feasters channel Feast on the Aegis, draining its power and making the shielded area smaller.
    • Spread out at least 4-yards from other players to mitigate the damage from Felblaze Imp's Fel Blast.

Stage 3 - the final onslaught

  • This stage only occurs on Mythic difficulty.
  • At 33% health, four portals are opened allowing Felblaze Mistresses and Felblaze Feasters to enter the fight.
    • Felblaze Feasters act the same as in Stage 2.
    • Don't stand near Felblaze Mistresses to avoid Shadow Sweep.

Healer DBM settings for Domatrax

Mephistroth Dungeon Journal ModelMephistroth

This is a two-stage fight where you fight against Mephistroth and use the Aegis of Aggramar to defend Illidan.

Stage 1 - mephistroth

Stage 2 - fades into shadow

At full energy, Mephistroth casts Shadow Fade, starting Stage 2.

  • The group takes steadily increasing damage from Creeping Shadows.
  • Illidan Stormrage appears in the middle of the room and attempts to reveal Mephistroth with Expel Shadows.
    • The tank should pick up the Aegis of Aggramar and use it to protect Illidan from Shadow Blast orbs.
    • DPS should kill the Shadows of Mephistroth around the edges of the room.
  • Dreadwings appear during this Stage as well and cast Fel Blaze on random players.

Healer DBM settings for Mephistroth

Debuffs to Track


Thrashbite the Scornful

  • (Optional) Beguiling Biography can be tracked so you know which player is charmed and unable to be healed.


  • There are no particular debuffs to track.


  • (Optional) Dark Solitude can be tracked so you know who will need additional healing from the damage over time effect.

Comment on "Cathedral of Eternal Night, Healer Guide"


September 05, 2017 (Cathedral of Eternal Night) - Guide reviewed for patch 7.3, no changes needed.

June 13, 2017 (Cathedral of Eternal Night) - Reviewed for patch 7.2.5, no changes needed.

April 16, 2017 (Cathedral of Eternal Night) - Added DBM settings to healer guide and added optional debuff to track to Mephistroth.

March 27, 2017 (Cathedral of Eternal Night) - Reviewed for patch 7.2 launch, no changes made.

March 03, 2017 (Cathedral of Eternal Night) - Healer guide created.

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