The Jailer, Healer Guide
Updated 1 month, 2 weeks ago for patch 9.2 by Preston. View the change log.
This page covers a healer-focused strategy for The Jailer in Sepulcher of the First Ones in Shadowlands. 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 encounter, combat log information, and Dungeon Journal information. I'll continue to update it as-needed.
General Mechanics and Abilities
Normal and Heroic
Stage One - Origin of Domination
This stage begins the encounter and ends when The Jailer has control over all Control Pylons through the use of 
Relentless Domination.
- The tanks will be dealing with
Martyrdom, fixating the current tank and performing a series of attacks.
Imprisonment roots the tank in place.
Persecution deals moderate damage and greatly increases Physical damage taken.
Suffering deals light damage and then light damage over time to all players.- At least five players must stack with the tank to split the damage from
Misery.
- When affected by
Rune of Damnation, jump inside a Control Pylon hole just before the effect expires to prevent the light damage dealt to and knock back effect on all players. - When targeted by
Torment, move at least 5-yards away from other players. - During
Relentless Domination, break line of sight on The Jailer using a deployed Control Pylon.
- Players in line of sight are mind controlled by
Domination, gaining greatly increased health and damage dealt. - On Heroic, avoid the path of players targeted by
Tyranny.
- Players hit take light damage and stacking light to moderate damage over time.
- Players in line of sight are mind controlled by
- During
Chains of Oppression, run against the pull to remain as far away as possible to lessen the damage taken from 
Oppression.
Stage Two - Unholy Attunement
This stage begins when The Jailer has control over all Control Pylons and ends when a set of Control Pylons successfully link from the edge of the platform to the Machine of Origination in the center.
- The tanks will be dealing with
Shattering Blast, dealing light damage over time to all players and destroying any Control Pylons within 10-yards.
- The goal is to keep the Control Pylons from successfully linking for as long as possible.
- When affected by
Rune of Compulsion, move as far away from the edges of the platform as possible before the effect expires.
- Affected players become hostile and gain a damage absorption shield that must be broken before they're forced to jump off the edge of the platform.
- During
Unholy Attunement:
- Deals light to moderate damage to all players with
Unholy Eruption, depending on the proximity of the Control Pylons to the Machine of Origination. - Avoid the
Unholy Ground around Control Pylons.
- Deals light to moderate damage to all players with
- Avoid the impact location of
Decimator. This knocks back and deals light damage over time to all players. - Avoid the additional
Tormenting Echo impact locations left behind after Torment.
Stage Three - Eternity's End
This stage begins when a set of Control Pylons successfully link from the edge of the platform to the Machine of Origination in the center and ends when The Jailer is killed.
- Stack with the player affected by
Rune of Domination to split the healing absorption effect from 
Dominating Will.
- The healing absorption from Dominating Will must be depleted before the effect expires, or players will be mind controlled by Domination.
- The healing absorption from
- When affected by
Chains of Anguish, run more than 30-yards away from the linked player to break the effect.
- Breaking a Chain deals moderate damage to all players with Chain Breaker.
- Breaking a Chain deals moderate damage to all players with
- During
Desolation, stand in the impact location to reduce the damage dealt to Azeroth. Players in the impact take moderate damage. - Torment now also spawns an Incarnation of Torment.
- Incarnation of Torment
- Deals increasing light damage to all players and applies stacks of haste reduction with
Cry of Loathing.
- Deals increasing light damage to all players and applies stacks of haste reduction with
- Incarnation of Torment
- Avoid the impact location of Decimator. This knocks back and deals light damage over time to all players.
- Avoid the impact locations of
Falling Debris. - Avoid the locations of
Defile. Each time a player is damaged by Defile, its size grows.
Mythic Differences
Stage One - Origin of Domination
- Deals heavy damage and applies
Arcane Vulnerability to all players with 
World Crusher.
- Creates a
Blood of Azeroth pool.
- Standing in the pool repeatedly chains
Surging Azerite to the closest player within 13-yards, and will heal Azeroth if a chain of players brings the chain within range.
- Applies stacks of Azerite Radiation to all players hit, greatly increasing Arcane damage taken while increasing damage and healing done.
- This gradually shrinks the Blood of Azeroth pool.
- Applies stacks of
- Standing in the pool repeatedly chains
- Creates a
- During Martyrdom:
- Players hit by Misery gain
Relentless Misery, greatly increasing damage taken from subsequent Misery hits while the effect persists.
- Players hit by
- Players with two stacks of Torment are mind controlled by Domination.
Stage Two - Unholy Attunement
- Deals light damage to all players with
World Cracker.
- Creates a Blood of Azeroth pool, which functions similarly to stage one, with the following addition.
- Avoid the path of
Tainted Azerite energy emanating from players hit by Surging Azerite.
- Avoid the path of
- Creates a
- During Unholy Attunement:
- Consumes remaining Blood of Azeroth pools, gaining a large damage absorption shield from
Consumed Azerite.
- Consumes remaining
Stage Three - Eternity's End
This stage begins as usual, when a set of Control Pylons successfully link from the edge of the platform to the Machine of Origination in the center, but now ends when The Jailer reaches 10% health.
- Deals critical damage to all players with
World Shatterer.
- Creates a Blood of Azeroth pool, which functions similarly to stage one.
- Creates a
- The size of Defile now also grows slowly over time.
Stage Four
This stage begins when The Jailer reaches 10% health, at which point he heals to 24% health, and ends when he's killed.
- Rune of Damnation, Decimator, and Falling Debris continue during this stage.
- Gains a massive damage absorption shield from
Diverted Life Shield. - Dispel
Death Sentence (magic) in a controlled manner, before the effect expires.
- When dispelled, one player must stand in each of the two impact locations to prevent all players from gaining Death Sentence (dispel, magic).
- Players are killed if they gain two stacks of Death Sentence (dispel, magic).
- When dispelled, one player must stand in each of the two impact locations to prevent all players from gaining
- During
Meteor Cleave, stand in front to split the damage dealt. Players hit take greatly increased damage from subsequent Meteor Cleaves while the effect persists. - Torment now spawns additional pools of Defile instead of Incarnation of Torment.
Healing Notes
Quick Notes, All Difficulties
The notes below mostly pertain to progression difficulty, meaning if you out-gear the difficulty you're on or use extra healers they may not apply.
- Use Major Cooldowns on
- Martyrdom [occurs about every 45-seconds in stage one]
- Unholy Attunement [occurs about every 45-seconds in stage two]
- Chains of Anguish [occurs about every 45-seconds in stage three]
- (Mythic) World Shatterer
- Use Minor Cooldowns on
- Torment [occurs about every 45-seconds]
- Dominating Will
- Pre-heal Before (mainly for heal over time classes)
Potion of Spiritual Clarity use
- likely during stage two when not selected by Rune of Compulsion
- likely during stage two when not selected by
- Other things to watch for
- I'll update this section as-needed.
Debuffs to Track
Major
- Dominating Will causes players to absorb healing, and must be depleted quickly.
- Chains of Anguish can cause players to need additional healing.
- (Mythic) Death Sentence (dispel, magic) should be dispelled in a controlled manner, and causes players to need increasing light to moderate healing over time.
Minor
- Several abilities cause players to need light healing over time.
Useful Addons
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