Rygelon, 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 Rygelon 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
- The tanks will be dealing with
Corrupted Strikes, which requires use of active mitigation to avoid gaining excessive stacks of 
Corrupted Wound. - Unstable Matter spheres appear near pylons on the edges of the room.
- Unstable Matter
- When killed, leaves behind several
Unstable Matter Fields, used to deal with 
Massive Bang, detailed below.
- When killed, leaves behind several
- Unstable Matter
- During
Celestial Collapse, six Collapsing Quasars spawn on the six anima-infused patches circling the center of the room.
- Collapsing Quasar
- Attempts to reach Rygelon, increasing its damage dealt and dealing stacking light damage over time to all players with
Quasar Radiation. - Upon death, leaves behind a
Collapsing Quasar Field.
- This is used to deal with
Dark Eclipse, detailed below. - After entering the field, stay more than 5-yards away from other players to avoid chaining the damage from
Event Horizon.
- This is used to deal with
- On Heroic, gradually gains stacks of
Accretion, increasing movement speed and reducing effectiveness of slow effects.
- Attempts to reach Rygelon, increasing its damage dealt and dealing stacking light damage over time to all players with
- Collapsing Quasar
- On Heroic, during
Manifest Cosmos, one Cosmic Core spawns.
- Cosmic Core
- Targets the nearest player with
Cosmic Ejection, dealing stacking moderate to heavy damage over time to all players within 5-yards.
- Targets the nearest player with
- Cosmic Core
- When affected by Dark Eclipse:
- Briefly move into a Collapsing Quasar Field to remove the effect and avoid dealing moderate damage to all players with
Dark Eruption when the effect expires.
- This instead deals light damage to all players with
Dark Collapse. - On Heroic, the Collapsing Quasar Field is consumed.
- This instead deals light damage to all players with
- Briefly move into a
- During Massive Bang, run against the pull to remain inside an Unstable Matter Field to enter The Singularity.
- While inside The Singularity:
- Deals increasing light to moderate damage over time to all players with
Eternal Radiation. 
Shatter Sphere triggers Unstable Antimatter, removing all players from The Singularity while dealing stacking light damage over time.
- On Heroic, this deals fatal damage to all players if a Cosmic Core is still alive.
- On Heroic, Cosmic Cores are present from outside The Singularity.
- Cosmic Core
- Players must stand within 5-yards to be damaged by
Stellar Decay, which in turn damages the Core. - Upon death, a tank must stand within 8-yards to take the heavy damage and heavy damage over time from
Gravitational Collapse.
- If no player is hit, the effect instead hits all players.
- Players must stand within 5-yards to be damaged by
- Cosmic Core
- Deals increasing light to moderate damage over time to all players with
- While inside
- Avoid the lines of
Celestial Terminator. - If no players are available to be targeted,
Radiant Plasma deals moderate damage over time to all players until a target is available.
Mythic Differences
- Manifest Cosmos now summons three Cosmic Cores.
- Cosmic Core
- Applies stacks of
Cosmic Irregularity to targeted players, dealing increasing light damage over time and kills any players that reach six stacks.
- Applies stacks of
- Cosmic Core
Stellar Shroud deals light damage to all players and absorbs a moderate amount of healing on all players.- While inside The Singularity:
- Avoid the impact locations of
Dark Quasar. - Cosmic Core
- Stellar Decay now increases damage taken from subsequent hits of Stellar Decay.
- Avoid the impact locations of
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
- while inside The Singularity [occurs about every 1-minute 45-seconds]
- while inside
- Use Minor Cooldowns on
- Dark Eclipse/Dark Collapse [occurs about every 2-minutes]
- (Mythic) Stellar Shroud
- Pre-heal Before (mainly for heal over time classes)
- entering The Singularity
- Dark Eclipse/Dark Collapse
- entering
Potion of Spiritual Clarity use
- immediately after leaving The Singularity
- immediately after leaving
- Other things to watch for
- Healing required is high and persistent for most of the encounter.
Debuffs to Track
Major
- Corrupted Wound causes the tanks to need light to moderate healing over time.
- Gravitational Collapse causes the tanks to need heavy healing over time.
- Dark Eclipse causes players to need light healing over time, and will deal moderate damage to all players if the affected player dies.
Minor
- Cosmic Ejection causes players to need light to moderate healing over time.
- (Mythic) Cosmic Irregularity causes players to need light healing over time.
Useful Addons
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