Legion Boss Guide: Il'gynoth, Heart of Corruption

As usually, these tactics are my own and does not mean they are the most optimal. 

Background Story

Lodged in the hollows of a now-decrepit world tree, Il´gynoth is a manifestation of the horrors that lie at the heart of the Nightmare. It is a mass of corruption – a thing that should not be. Its tendrils seep through the ground, emerging in countless horrifying eyestalks and limbs.

 

Overview

This boss is inside a tree and one of his eyes is blocking the entrance of the tree.
Your job is to enter the tree and kill the boss.
To do that, the eye needs to be nuked first.
The only way to damage the big eye is to kill a certain add (Nightmare Ichor) close to the eye.
This add spawns by killing the other adds which are tentacles and a Nightmare Horror.
Once inside you have 50 seconds to go nuts on boss but if you don’t exit the tree after 50 seconds you will die.
When you exit an eye will block the entrance again.
Rinse and repeat.

 

Tactics

This fight is divided in two phases.
Phase 1 – Fight adds that spawn in which some needs to be killed on the big eye.

Phase 2 – Fight the boss inside the tree.

PHASE 1 – Add phase

The big eye has too much defense to nuke it.
The only way to damage the big eye is to kill a certain add (Nightmare Ichor) close to the eye.

In total, there are 5 types of adds

Nightmare Ichor (Blob)
Dominator Tentacle (Stationary)
Deathglare Tentacle (Stationary)
Corruptor Tentacle(Stationary)
Nightmare Horror (mobile)

Nightmare Ichor ads (blobs) will spawn whenever the other adds die:
* 2 blobs spawn when a tentacle is dead
* 4 blobs spawn when a Nightmare Horror is dead

A total of 20 Nightmare Ichors need to blow up on the eye in order to enter phase 2.
The blobs need to be kited until it is time to collect them all near the eye and AoE them down.

 

Phase 1 is divided in 3 sets of add spawns. Below you will find the number of tentacles spawning on first phase 1. The more times you enter phase 1, the more amount off Deathglare and Corruptor tentacles will spawn on each set.

SET 1

2 Dominators at start
1 Deathglare after a short time

After both dominators are dead and Deathglare is dead you will have 6 blobs
Move to eye and AoE the blobs down (move away before they explode).

Tactics – Dominator Tentacle

At the start of the fight and every time after you exit phase 2 (start of phase 1), there are two of this tentacle.
The second time they spawn (after phase 2 ends) they spawn further down.

Tanks

One tank on left dominator
One tank on right dominator
Phase the add towards the wall on boss side alternative opposite side depending on where they spawn later.

Raid

Divide the melee in two groups (make sure it is one melee dps in each group)

Group 1 melee on left dominator behind add.
Group 2 melee on right dominator behind add.

Ranged spread behind the add.

When targeted by slam
Move to the side of a dominator (doesn’t matter what side).

In this way you will leave the entire front and back side of the add free, and slams will only hit the sides of the adds.

When Dominator does Nightmarish Fury
Tank use mitigation (defensive cooldown).

Tactics – Deathglare tentacle

DPS
Melee DPS on this add (ranged as filler)
Interrupt the Mind Flay

Healers
Dispel the Mind Flay
Heal /shield the player targeted by this Mind Flay if not dispelled.

Raid
If targeted by mind flay and not dispelled, use a defensive cd

Set 2

One Nightmare Horror spawns

Tentacles will spawn shortly after the Nightmare Horror
Right side

1 Deathglare
1 Corruptor

Left side

1 Deathglare
1 Corruptor

Tactics – Nightmare Horror

DPS
Nuke this add but shift to tentacles (Deathglare and Corruptors) when they spawn.

Tanks  
Tank swap every 2 stacks.
Tank the add on the top right side of the platform and move the add downwards every time he creates a shadow pool.

Alternative: Bring the Nightmare Horror to the tentacles for cleave damage but beware of the pools that the Horror creates.

Healers
Use defensive on tank when add does Eye of Fate if needed.

Raid
Do not stand in front of this add.

Tactics – Deathglare tentacle

DPS
Melee DPS on this add (ranged as filler)
Interrupt the Mind Flay

Healers
Dispel the Mind Flay
Heal /shield the player targeted by this Mind Flay if not dispelled.

Raid
If targeted by mind flay and not dispelled, use a defensive cd

Tactics – Corruptor Tentacle

Ranged DPS only on this add (melee as filler)
Everyone stay away from this add so you don´t get hit by it.

If targeted by spew corruption, run fast to the side(closest) and place all the pools there, then run back when all 5 pools have been created.

When tentacles are dead, go back and nuke the horror.  

After this set of adds are dead you will have 12 Blobs.
Move to eye and AoE them down (move away before they explode).

Alternative – nuke blobs from tentacles before finishing of the Horror add then nuke the 4 blobs from it.

Set 3 (and set 4 if eye not killed)

1 Deathglare
1 Corruptor

Tactics – Deathglare tentacle

DPS
Melee DPS on this add (ranged as filler)
Interrupt the Mind Flay

Healers
Dispel the Mind Flay
Heal /shield the player targeted by this Mind Flay if not dispelled.

Raid
If targeted by mind flay and not dispelled, use a defensive cd

Tactics – Corruptor Tentacle

Ranged DPS only on this add (melee as filler)
Everyone stay away from this add so you don´t get hit by it.

If targeted by spew corruption, run fast to the side(closest) and place all the pools there, then run back when all 5 pools have been created.

Nuke tentacles down then move to eye with blobs and AoE them down (move away before they explode).

You can nuke blobs already after killing 1 of the tentacles since you will be up to 20 blobs which is required to enter the tree. But you have to kill the other tentacles anyway since they will not disappear. Also, the blobs need to die before entering since they will instant explode if they enter the tree as well when following you.

 

PHASE 2 – Boss

When 20 blobs have exploded on the eye, it will move away and the entry to the tree is open.

Inside lies the boss and you have 50 seconds to attack boss. If you don’t exit before the timer is over you will die.

The timer (Dark Reconstitution) starts when you actually enter the tree.

Tactics Phase 2

Make sure all blobs and adds are dead before entering the tree.

Bloodlust/Timewarp on this phase and burn the boss down.

Raid

Entire raid hugs the boss so you are in close melee range.

If/when you get the debuff Cursed blood – run to the wall and wait until explosion, then run back in again.

Everyone exit the tree before Dark Reconstitution is over or you will die instantly.

 

 

ABILITES

The Eye

The eye has 2 abilities

Stuff of Nightmares

The Eye takes 99% reduced damage from all sources, excluding Nightmare Explosions, which deal full damage to it.

Nightmare Gaze

The eye fixes a dark Gaze on a player, inflicting 800k shadow damage to the player.

The adds

Dominator tentacle

This add is stationary and has 3 abilities.

Ground Slam
Slams the ground in the direction of a targeted player doing physical damage to all players in a line and knocking them back.

Nightmarish Fury
The add does several fast attacks (every 0.8 for 6 seconds) in which each attack does around 1 mill damage.

Rupturing Roar
The add does a roar if not being melee attacked, doing Physical damage to all players.

Deathglare Tentacle

This is a stationary add and has one ability (Mind Flay)
Targets a player and does high damage every 2 sec of 8 sec.

Corruptor Tentacle

This add is stationary and has one ability (Spew Corruption)
Attacks nearby players with spew corruption which does shadow damage AND puts a debuff on that player.

This debuff causes the player to create Nightmare Corruption pools every 2 seconds for 10 seconds (5 pools). Standing in this pool does Shadow damage.

Nightmare Horror

This add has two abilities:

Eye of Fate
Shoots a “laser” in front of the add which does very high damage and increase damage taken from that laser by 20% for 30 seconds.

Sleeping Corruption
This add creates pools periodically underneath them.

Nightmare Ichor

This blob spawns every time the other adds are killed.
* 2 blobs spawn when a tentacle is dead
* 4 blobs spawn when a Nightmare Horror is dead

This blob fixates a player and if the blob comes close (melee range) it will put a dot on the player causing Shadow damage every 2 sec (stacking effect) called Touch of Corruption.

When the blob is killed, it will explode and do damage to nearby players. This explosion will also do damage on boss.

The boss

The boss has 4 abilities

Dark Reconstitution

When entering the tree, the boss starts casting this ability which takes 1 minute to cast. Once casted he unleashes energy that kills all players inside the tree.

Cursed Blood

The boss puts a debuff on several players which does shadow damage every 2 seconds and detonates after 8 seconds. The detonation does very high damage to players within 11 yards.

Reabsorption

If blobs enter the tree, they will blow up and do shadow damage to all players.

Final Torpor

Boss gets tired of you and gather all his energy of the Nightmare to kill any living thing - instant kill.

14 Aug 2016