TheWoWDBAberrus, the Shadowed Crucible
The Forgotten Experiments Guide
The Forgotten Experiments in Aberrus, the Shadowed Crucible, quoted from the Adventure Guide. Database holds the raw abilities and the full loot table.
30-second TL;DR
Adventure Guide says
- The forgotten experiments within Neltharion's laboratory each represent a dark stage in the development of the dracthyr.
- Neldris enters the fray first and assaults the laboratory's intruders with Rending Charge.
- Tanks: Infused Strikes inflict increasing Arcane damage.
- Healers: Neldris' Rending Charge inflicts heavy bleed damage on several targets.
- Damage dealers: Neldris dashes between marked players with Rending Charge, affecting anyone in her path.
Overview
Adventure Guide says
The forgotten experiments within Neltharion's laboratory each represent a dark stage in the development of the dracthyr. Neldris enters the fray first and assaults the laboratory's intruders with Rending Charge. Upon Neldris' defeat, Thadrion bursts from his containment vat, afflicting players with Unstable Essence and belching forth Volatile Spew. As Rionthus' predecessor is defeated, he escapes his containment vat and begins to devastate the chamber with Neltharion's most potent version of Deep Breath.
- Infused Strikes inflict increasing Arcane damage.
- Rionthus soars across the room during Deep Breath.
- Neldris dashes between marked players with Rending Charge, affecting anyone in her path.
- Unstable Essence creates an explosion upon removal and jumps to a nearby player.
- Rionthus gains a shield that absorbs damage if Temporal Anomalies reach him.
- Neldris' Rending Charge inflicts heavy bleed damage on several targets.
- Violent Eruption inflicts heavy damage to all players.
- Unstable Essence creates an explosion upon removal and jumps to a nearby player.
Tank mechanics
Adventure Guide says
- Infused Strikes inflict increasing Arcane damage.
- Rionthus soars across the room during Deep Breath.
Healer mechanics
Adventure Guide says
- Neldris' Rending Charge inflicts heavy bleed damage on several targets.
- Violent Eruption inflicts heavy damage to all players.
- Unstable Essence creates an explosion upon removal and jumps to a nearby player.
DPS mechanics
Adventure Guide says
- Neldris dashes between marked players with Rending Charge, affecting anyone in her path.
- Unstable Essence creates an explosion upon removal and jumps to a nearby player.
- Rionthus gains a shield that absorbs damage if Temporal Anomalies reach him.
Boss abilities
| Ability | Adventure Guide | Notes |
|---|---|---|
| Zealous Creations | ||
 Rending Charge | In Mythic difficulty, Rending Charge does not expire. | |
 Massive Slam | ||
 Bellowing Roar | ||
 Infused Strikes | ||
 Infused Explosion | ||
 Unstable Essence | In Heroic difficulty, an Erratic Remnant is formed when Unstable Essence is removed and Unstable Essence persists after Thadrion's demise. | |
 Volatile Spew | ||
 Violent Eruption | In Heroic difficulty, Erratic Remnants inflict Arcane damage to all players during Violent Eruption. | |
 Deep Breath | ||
 Temporal Anomaly | In Mythic difficulty, Temporal Anomalies apply Temporal Fracture. | |
 Temporal Fracture | ||
 Disintegrate |
Loot
Every name is a TheWoWDB item page. Hover the row for the first-party tooltip.
Discarded Creation's Restraint
Dreadful Mixing Fluid
Dreadful Quickened Bronzestone
Exacting Augmenter's Sabatons
Experiment 1, Kitewing
Manacles of Cruel ProgressMystic Mixing FluidMystic Quickened Bronzestone
Neldris's Sinewy Scapula
Ominous Chromatic Essence
Rionthus's Bladed Visage
Thadrion's Erratic ArcanotrodeVenerated Mixing FluidVenerated Quickened BronzestoneZenith Mixing FluidZenith Quickened Bronzestone
Pattern: Undulating SporecloakMounts, toys, achievements, transmog
Only rows the journal loot table or an achievement title can prove for this encounter.
Achievements
Aberrus, the Shadowed Crucible · Heroic: Aberrus, the Shadowed Crucible · Mythic: Aberrus, the Shadowed Crucible · Mythic: Assault of the Zaqali · Mythic: Echo of Neltharion · Mythic: Kazzara, the Hellforged · Mythic: Magmorax · Mythic: Rashok, the Elder · Mythic: Scalecommander Sarkareth · Mythic: The Amalgamation Chamber · Mythic: The Forgotten Experiments · Mythic: The Vigilant Steward, Zskarn
Entrance and instance
Aberrus, the Shadowed Crucible is a raid in the Adventure Guide. See the Aberrus, the Shadowed Crucible database page for the raw journal, map, and loot grid. This guide does not invent coordinates or a walking path.
Related bosses
Player strategy
This page quotes the Adventure Guide. It does not add player strategy such as positioning, assignments, stack or spread calls, or cooldown timings unless that sentence is already in the journal.
Questions
What does the Adventure Guide say about The Forgotten Experiments?
The forgotten experiments within Neltharion's laboratory each represent a dark stage in the development of the dracthyr.
How many abilities does The Forgotten Experiments have?
The current datamine lists 12 named abilities on the The Forgotten Experiments encounter.
What does The Forgotten Experiments drop?
The Adventure Guide lists 17 drops. Each name links to its TheWoWDB item page. The full table also lives on the Aberrus, the Shadowed Crucible database page.
Does The Forgotten Experiments change on Heroic or Mythic?
The current Adventure Guide text for this encounter does not include separate Heroic or Mythic sentences we can quote. If a later client build adds them, they appear here automatically.
Where does this guide's text come from?
Quoted Adventure Guide sections come from TheWoWDB's retail datamine (client build 12.1.0.69587, ingested 2026-09-01). Player strategy such as positioning, assignments, and cooldown timings is omitted unless that sentence is already in the journal.
Source and build
This page quotes the Adventure Guide. It does not add player strategy such as positioning, assignments, stack or spread calls, or cooldown timings unless that sentence is already in the journal. Quoted sections come from TheWoWDB Adventure Guide datamine (client build 12.1.0.69587, ingested 2026-09-01). Ability names link to first-party spell pages. When a newer retail build is ingested, this page updates with it.