Glory of the Sepulcher Raider

Vigilant Guardian - Power ON
- Power up and kill the [npc=184759] before defeating the boss.
- Before pull, use a Death Knight to grip the inactive add into the boss arena. Add location.
- Pull the boss and kill adds near the [npc=184759] to activate it.
- Once active, kill it and then defeat the boss.

Skolex - Wisdom Comes From the Desert
- Destroy 4 Memorial Pylons in the order indicated by their tooltips.
- Pylons are destroyed by baiting [spell=359770] under them. Order of destruction.
- Tooltip order: In memory of Liet... -> ...Researcher of the Ravener... -> ...who dubbed the name "Skolex"... -> ...and was then eaten by it.

Xy'mox - Xy Never, Ever Marks the Spot.
- Collect 3 artifacts for 3 debuffs and then defeat Xy'mox with ALL players under the effects of ALL debuffs.
- Artifact Locations. Need movement ability to reach. Only a single player needs to interact with each artifact.
- Artifacts spawn one by one: On pull / 75% / 50%. Debuffs: [spell=367220], [spell=367275], [spell=367278]
- Assigning players to the artifacts is recommended. Demon hunters are great.
- Do not use any ability that remove slows. This will remove the slow debuff and fail the achievement.
- Death does not remove debuffs.

Halondrus - Shimmering Secrets
- Pick up and bring 6 [npc=184823] to the final room. Each artifact spawns an add, kill them and defeat the boss.
- Artifact Locations. Credit to: Shase#7617 (discord)
- Assigning players to the artifacts is recommended. Mobile classes are great. Ability to deal with knockbacks is a huge bonus.

Dausegne - Four Ring Circus
- Defeat Dausegne while a player is carrying an [npc=185074].
- [npc=185074] is dropped by a [npc=183406] in one of these locations.
- [npc=185074] applies a slow and is destroyed if hit by [spell=361751].
- Assigning a mage is recommended.

Prototype Pantheon - Where the Wild Corgis Are
- Defeat Prototype Pantheon while every player has at least 5 stacks of [spell=367322].
- Interact with [npc=185479] before pulling the boss. Location.
- Interact with Corgis during [spell=361305] in Phase 2. Each completed pet cast grants a stack of [spell=367322] to everyone within 15 yards.

Lihuvim - The Protoform Matrix
- Synthesize a [npc=185423], kill it and then defeat the boss.
- Before pulling, use Summon Reaves near an unsynthesized Protoform Automa.
- Locations: A & B. A: Summon Reaves before pull. B: Kill during first [spell=363130].
- Pull the boss. Let Reaves be synthesized. Kill Reaves and then defeat the boss.

Anduin - Coming to Terms
- Collect 3 [npc=185766] before pulling the boss. Kill [npc=185005] in a [spell=362405] phase. Then defeat the boss.
- Haunting Memory Locations. Credit to: Shase#7617 (discord)
- You only have to kill [npc=185005] once.

Lords of Dread - Amidst Ourselves
- Complete a simple puzzle during an [spell=360417].
- Puzzle: Simple "Lights Out"-style game. Interacting any of the lights will toggle it and the adjacent lights.
- Goal: Switch on all the lights. Only 1 completion needed.
- Possible game locations.

Rygelon - We Are All Made of Stars
- Defeat Rygelon while the entire raid is affected by [spell=366195].
- Have all players stand in any one of these locations when pulling the boss.
- If done correctly, everyone will be transformed into a celestial and get the [spell=366195] debuff.
- Any player death will fail the achievement for the raid.
- New ability - Phase 1: [spell=366206] - Indicated by a small purple/pink swirly.
- New ability - Phase 1: [spell=366213] - Indicated by a large white swirly.
- New Ability - Phase 2: [spell=366231] - Indicated by a large white swirly.

The Jailer - Damnation Aviation
- Collect all 6 Progenitor Orbs in Phase 1. Defeat the boss.
- Orb Locations / Orb Image (by YariniCeteri). Orbs float high above the arena. Placing world markers is recommended.
- Use the knockup from [spell=360282] to reach. You get knocked upwards and backwards. Orbs are only visible while the runes are active.
- Collect at least 1 orb per set of [spell=360282]. There are 6 orbs and exactly 6 sets of runes.
- Safe method: Have all 3 players affected by runes go for the same orb every time. Group on a world marker and walk into the 3 nearby holes. Correct sides are marked white in the locations image.

Heyo
I did a simple text guide with some pics where needed for anyone interested in doing an early run. Pointed out some niche things and provided tips from my run.

The guide follows a simple format, that being:

Title/boss
Something really important
The how-to text itself

For any questions, you can dm me on discord Dado#6124

Excellent guide, straight to the point, useful images and links, and great formatting making it easy to read. If I could upvote this twice I would.