This page covers a healer-focused strategy for the Cenarius in The Emerald Nightmare. 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

This is a two-stage fight. Stage 1 happens when Cenarius is above 30% health and there are still Forces of Nightmare to be killed. Stage 2 happens when all Forces of Nightmare are killed or Cenarius reaches 30%.

Stage 1 - nightmare adds

• Creeping Nightmares applies an unavoidable stacking damage over time effect. Be prepared to use a personal cooldown if your stacks get too high.
• Avoid Nightmare Brambles, if you touch one and become rooted it should be dispelled or otherwise removed.
• Forces of Nightmare will spawn from Nightmare Seeds if they are not cleansed with in 10-seconds of Cenarius spawning them. You can only cleanse one Nightmare Seed per round.
  • Avoid being hit by the Wisps or you'll take damage from Destructive Nightmares.
  • If no players are within 8-yards of the add, Desiccation will happen instead.
  • It will randomly target players with Rotten Breath. Do not stand in the Breath.
  • At 50% health, it will begin casting Nightmare Buffet and needs to be killed quickly.
  • If a Nightmare Javelin is thrown at you, move at least 4-yards away from other players.
  • Twisted Touch of Life needs to be interrupted, if an enemy receives the heal over time effect it should be purged quickly.
  • Move at least 8-yards from other players if you're affected by Scorned Touch.
  • On Normal, the aura extends 20-yards around Cenarius.
  • On Heroic, the aura extends 30-yards around Cenarius.
• If Tormented Souls are not cleansed, Corrupted Wisps will spawn at the edge of the room.
• If Nightmare Saplings are not cleasned, they will spawn a Nightmare Ancient.
• It will cast Desiccating Stomp when it reaches 100 energy. You will likely want most of your group to stack with 8-yards of the add to mitigate the damage.
• If Corrupted Emerald Eggs are not cleansed, a Rotten Drake will spawn. 
• If Corrupted Nature are not cleaned, a Twisted Sister will spawn. 
• The Nightmare Forces will be affected by Aura of Dread Thorns from Cenarius.
• Malfurion Stormrage will provide assistance in this phase.
  • Try to avoid lingering in the Cleansed Ground too long or it will disappear more quickly.
  • It is recommended that you only clear your Creeping Nightmares stacks when you reach 30.
• He will use Cleansing Ground on Nightmare Seeds with the most players with in 12-yards of them. This will prevent them from spawning Force of Nightmare and instead spawn an Ally of Nature.
• Touching the Cleansed Ground will remove any existing stacks of Creeping Nightmares. The ground will eventually disappear as more players touch it and it removes more stacks.
• If you cleanse a Nightmare Seed, you will recieve one of the following Allies of Nature instead.
  • They will use Cleansing Detonate. This leaves behind Cleansed Ground.
  • It will periodically cast Replenishing Roots, which healers should stand in.
  • It will cast Ancient Dream on one of the tanks.
  • She will cast Unbound Touch on random players, making them immune to shadow damage. This can be used to clear the Nightmare Brambles.
  • When Unbound Touch expires, it will apply Unbound Essence to players within 4-yards.
• If Tormented Souls are cleansed, it will spawn Wisps around the room.
• If Nightmare Saplings are cleansed, a Cleansed Ancient will spawn.
• If Corrupted Emerald Eggs are cleansed, an Emerald Drake will spawn.
• If Corrupted Nature is cleansed, it will spawn a Redeemed Sister.

Stage 2 - nightmare ends

When all of the Nightmare Forces have been killed, or when Cenarius reaches 30% health, Stage 2 will begin.

• Continue to avoid excessive stacks of Creeping Nightmares and being hit by Nightmare Brambles.
• Malfurion Stormrage will also assist in this phase.
• He will use Cleansing Ground on the largest group of players. The resulting effect functions the same as in Stage 1.
• Cenarius will cast Entangling Nightmares on Malfurion. It must be killed quickly before it kills Malfurion.

Mythic Differences

The information below covers the new abilities and strategies introduced in Mythic difficulty. In addition to new things, you can expect all previous abilities to hit significantly harder.

Stage 1 - nightmare adds

• Cenarius will use Nightmare Blast on the current tank, forcing a tank swap.
• The generally accepted strategy in this phase is to group up all the Forces of Nightmare on Cenarius, except for the Rotten Drakes, these will be tanked by a third tank in the back of the room.
• When Forces of Nightmare are out, the DPS will be taking massive damage due to Aura of Dread Thorns affecting most of the adds.
• The goal is to push Cenarius into Stage 2 before a third set of Forces of Nightmare.

Stage 2 - nightmare ends

• Avoid being hit by Beasts of Nightmare. These beasts form two walls and walk in a straight line across the room.

Healing Strategy

This fight consists of several damage sources that can be almost completely avoided if handled properly. With that being said, you should still be aware of situations that aren't going as planned.

• It's possible for players to take significant damage from Creeping Nightmares if they don't make it to Cleansed Ground consistently.
• If Corrupted Wisps are present, be ready for players to take damage from Destructive Nightmares.
• If a Nightmare Ancient is preset, be aware of the heavy damage caused by Desiccating Stomp.
• If a Twisted Sister is present, Nightmare Javelin should be dispelled, and players hit by Scorned Touch will need moderate to heavy healing.
• If a Cleansed Ancient is present, try to stand in its Replenishing Roots.
• On Mythic, the group will almost always be taking moderate to high damage, with the highest damage being when Forces of Nightmare are present and Aura of Dread Thorns is active. Your highest DPS will be taking the most damage.

 Debuffs to Track

Below are debuffs you should track on your raid frames.

• Nightmare Javelin causes the target to need moderate healing.
• (Optional) Creeping Nightmares could be useful to track so you know which players have high stacks of the debuff.

 DBM Settings

Below are the DBM settings I'll be using for Cenarius. 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 abilities, which will be added to this guide soon.

Healer DBM settings for Cenarius

 Videos

Heroic, Restoration Druid PoV

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

Mythic, Restoration Druid PoV

Below is a video of me and my guild defeating Cenarius on Mythic difficulty. Again, there is no commentary, only game sounds.

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