The newly opened City of Dalaran dungeon has its first secret: deep in the sewers, a purple rune room summons a hidden boss — Lyn the Ignored. The summoning chain spans two maps. Community-tested steps below.
Step 1: Get the Black Tome in Shadowfang Keep
Run Shadowfang Keep up to Archmage Arugal. After killing him, interact with the book on his table to receive the Black Tome. This item starts the whole chain.
Step 2: Convert it at Ambermill
Head to Ambermill, the Dalaran-controlled town in Silverpine Forest. Inside the keep you'll find the Ambermill Leyline Focus — use the Black Tome next to it and it converts into the Tome of Dalaran. This is the step that stumped the community for a while.
Step 3: Summon in the sewers
Enter the City of Dalaran dungeon, clear the first boss (Atrexis the Grave Knight), and continue into the sewer tunnel: don't turn right toward the surface — go straight to the end, where a purple rune room waits. Use the Tome of Dalaran there and Lyn appears after a short RP entrance that nods to Ragnaros ("Too soon...").
Two practical details: the Tome of Dalaran is not consumed on use and only has a 3-minute cooldown — after a wipe you don't need to redo the chain, just wait and re-summon; and the summoning room sits at the end of an easy-to-miss dead-end, so don't let the forks pull you away.
The chain is classic Forever: an old-world easter egg stitched into brand-new content. Related reading: the Horde attunement walkthrough (note Blizzard's clarification that full city access wasn't intended), more discoveries in the secrets and hidden quests roundup, and the dungeon itself in the dungeon atlas.
Source: Wowhead (community-tested write-up), published 2026-10-12. Player-tested flow.