The Warden or another companion must be equipped with the entire set of Legion of the Dead, including the Helm of the Legion. Then the character must interact with the Legion of the Dead Relic located in the center of the Legion's Mausoleum in the Dead Trenches. It is the same room where the helm is found.
By interacting with the relic, the Gangue shade is summoned which is a Boss-level enemy and the dwarves believe to be the corrupt part of the Stone. The shade must then be defeated in order to complete the quest. This also unlocks the Codex entry: The Gangue Shade.
Rewards EditDead Metal Bucket
Silverite (Tier 6)
Requires: 30 strength
+25 mental resistance, from the Gangue shade.
- pc users can use this mod to fix this bug.