Hellfire High Council Boss Guide

Thousands of Iron Horde orcs accepted the blood of Mannoroth, but none grew as powerful as the three that stand before you. Dia Darkwhisper, master of void magic and an outcast of the Shadowmoon, rose quickly to power—the left hand of Gul’dan. Gurtogg, with his insatiable hunger for blood, emerged the victor in hundreds of trials by combat. He has met his match only once, fighting Blademaster Jubei’thos to a draw. Tainted with fel sickness, they serve Gul’dan as both Highguard and Council of War.

Short tactic explanation before pull when in LFR or PUG raid, 
/RW (Raid warning)

/rw Kill Order: Gurtogg, Blademaster, Dia
/rw One tank on Dia (on cross)

/rw One tank on Gurtogg and Blademaster (on skull)
/rw Tank swap at 15-17 stacks Acidic Wound
/rw Ranged in middle (middle circle)
/rw BL/TW when Gurtogg is at 30%
/rw If you have the debuff “Mark of Necromancer” run far to side when Dia casts Reap!
/rw Dispell “Mark of Necromancer” when it hits yellow/red color.
/rw Move away when boss does Demolishing Leap
/rw Use defensive CD (help with def CD) when Gurtogg targets u (Fel rage).
/rw Dodge the Horrors!! When The room turns dark

Overview

Players will fight all three bosses at the same time (It´s like Iron Maidens in BRF).
Dia and Gurtogg will be tanked and Blademaster cannot be tanked.
Dia will be tanked away since she sields neaby allies.

All three bosses has a special ability they call “Final Hour” that they achieve at 30% which boosts one of their abilities.

Positioning

One tank on Dia (on cross)
One tank on Gurtogg and Blademaster (on skull)
Ranged in middle (middle circle)
Melee behing bosses

Kill Order

Attack Gurtogg while cleaving Blademaster.
Take Gurtogg to 30% first and then use Bloodlust/timewarp to kill him.
Make sure that Blademaster doesnt reach 30% before Gurtogg is dead.
The time to kill Gurtogg the last 30% is critical since he reduces the maximum HP on players by 10% and that stacks every time he does it.

After Gurtogg is dead, take down Blademaster to 30% and kill him fast.

Last boss is Dia, Bring her down to 30% and use dps cooldowns to kill her. Save so all players have defensive cooddowns for this part.

Use Timewarp/Bloodlust when Gurtogg is at 30% to reduce the Tainted Blood Stack.

 

General Tacts

Stack Gurtogg and Blademaster together 
One tank on Gurtogg
One tank on Dia
Tank swap between them when the tank on Gurtogg gets 15-17 stacks Acidic Wound
Use defensive cooldown then hit by Nightmare Visage (burst shadow dmg on tank)
Tank Dia away at cross marker, from the other bosses because of Void Haze (this shields herself and her allies)
Move away from Gurtogg when he jumps around and does demolishing leap (heavy AoE dmg the closer you are)


Extra healing when raid gets dmg from FelStorm (players targeted and getting fire dmg)
Extra heal on tank that is hit by Void Bolt (shadow dmg on tank)
Extra heal on tank that is hit by Nightmare Visage (burst shadow dmg on tank)
Extra heal on players affected by Mark of Necromancer (debuff that does dmg over time)
Dispel if players is getting to heavy dmg from Mark of Necromancer (when dispelling, it jumps to 2 other players)
Don’t stand on shadow pools after Reap.
Extra healing on players targeted with Bloodboil (five players furthest from boss gets dmg)
Extra heal and defensive cd on player targeted by Fel Rage (Gurtogg single focus hits that player)
Extra raid heal when Gurtogg does Demolishing Leap (jumps around and does heavy aoe dmg, the closer you are)
Move away from Gurtogg when he jumps around and does demolishing leap.
Avoid the Horrors.
When Dia will use Reap to remove the debuff, move to the side and place it there. 

Nuke 1 boss at a time and the other bosses takes cleave dmg.
When Blademaster´s Images are out, aoe them fast (not at final Hour, then single nuke the bosses in the right order)
Use defensive cd when having the Mark of Necromancer debuff.
Move away from Gurtogg when he jumps around and does demolishing leap.
Don’t stand on shadow pools after Reap.
Avoid the Horrors.
When Dia will use Reap to remove the debuff, move to the side and place it there. 

Abilities and Strategy

Blademaster Jubei’thos

Has 3 abilities (Fel Blade, Felstorm and Windwalk)

Fel Blade

Blademaster throws his sword away and if players are hit by it they suffer moderate damage.
Simply Dodge the burning blades.

FelStorm

Blademaster throws a fiery tempest at all players in raid.
Does low damage over time for 8 seconds

Healers heal the players back up again.
Nothing players can do to interrupt this.

Windwalk

Blademaster will create 3 images of himself. The boss is stealth during this time.
The images will disappear after 45 seconds or after all 3 are dead.
During this time, the images will have same abilities as the boss.

Dps AoE all the images which will have much lower health than the boss and take more damage than boss.
If you let them be during the whole 45 seconds, they will do a lot of unnecessary damage on raid.
Also, these images share health with the boss so dpsing adds and boss is damaged as well.

Blademaster´s final hour

The boss will vanish and summon loads of images.
When images are dead, the boss will be appear for a short time and then vanish again and summon loads of images.
This will continue until boss is dead.

Aoe all the images, then focus on boss when he appears.
Continue like this until boss is dead.

Dia Darkwhisper

Has 5 abilities (Void Bolt, Void Haze, Nightmare Visage, Mark of the Necromancer and Wailing Horror)

Void Bolt

Dia does moderate shadow damage on the tank

Use defensive cd if it´s too much dmg to often.

Void Haze
- Dia put a cloak on herself and the other bosses.
- This cloak absorbs all dmg if players stand within 25 yards of her.
- Dia´s dark attendance cloaks allies in a dark cloud absorbing all damage taken for as long as they stand within 25 yards of her.

Move Dia away to Blue and tank her there.

Nightmare Visage

The boss turns into a vision of nightmare and bursts attacks on the tank.

The one tanking the boss needs to use defensive cooldown here.

Mark of Necromancer

The boss puts a debuff on random players.
THere are 3 colors that the debuff can have, purple, yellow red.
This debuff increases Shadow damage over time.
If dispelled it will bounce to 2 other targets that stands closest.

Dia removes this debuff after a while with an ability called Reap.
This debuff falls on the ground and does moderate shadow dmg on anyone standing on it.

Let the debuff tick on a player and debuff that player when dmg gets too high.

Purple color does low dmg on the player
Yellow color does moderate dmg on the player
Red color does high dmg on the player.

Dispell a player at yellow/red color. 

Move to the wall on the side before Reap so the shadow pool is placed away form the fight.

Wailing Horror

The boss covers the room in darkness and does moderate/high shadow damage on all players every second.
This darkness accumulates in random locations which creates Wailing horrors that will fly across the room.
Players in contact with these horrors will do moderate/high damage on them.

HOTFIX: Reduced the damage of Dia Darkwhisper's  Wailing Horrors by 30% on Normal difficulty.

Dodge the Horrors.

Dia´s Final Hour

Dia will put Mark of the Necromancer debuff on 50% of the players without any Reap to take it away.
The mark of the Necromancer stays until the entire encounter is done.

Gurtogg Bloodboil

This boss has 4 abilities; Bloodboil. Acidic Wound, Fel Rage and Demolishing Leap).

Bloodboil

The 5 players furthest from boss gets moderate physical damage.

Acidic Wound

The Boss infects the tank with nature damage and reduce armor by 100 every 2 seconds. Lasts for 30 seconds and stacks up to 60 times.

Tank swap ability that goes pretty fast.
Since there are 2 bosses that needs to be tanked; The one tanking Dia swaps with the one tanking Gurtogg.
Tank swap at 15-17 stacks.

Fel rage

Gurtogg rages and targets a random player.
That player gains extra defense.
If Gurtogg successfully hits the player, he gets 10% increased attack speed.

Even thou the player that gets targeted by Gurtogg gains a defensive ability, that player needs to use defensive CD. Healers should use some defensive cd on that player as well.

The defensive CD should be one(s) that disables Gurtogg to get a real hit, such as Ice block, Shield Absorb etc.

Demolishing Leap

The boss leaps around the room.
The landing impact does high/deadly Physical damage and aoe dmg.
The further away the player is from impact, the less dmg the players takes.

Move away from the landing impact/stand far away from landing impact

Gurtogg´s final hour

Gurtogg casts Tainted blood until he is dead.
Every Tainted blood reduces maximum health by 10%.
The blood stacks and will not go away until the whole encounter is over.

Other Boss Guides 

Hellfire Assault
Iron Reaver
Kormrok
Hellfire High Council
Kilrogg Deadeye  
Gorefiend
Shadow-Lord Iskar
Socrethar
 
Fel Lord Zakuun
Xhul'horac
Tyrant Velhari
Mannoroth
 
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