Secret boss found in the City of Dalaran: how to summon Lyn the Ignored
Beta testers found a secret boss in the new City of Dalaran dungeon: Lyn the Ignored, hidden in the sewers. To summon him you need a tome that you first have to find in Shadowfang Keep. Here is how.
Step 1: get the Black Tome in Shadowfang Keep
Clear Shadowfang Keep up to Archmage Arugal. After you beat him, a book on his table can be clicked. It gives you the Black Tome.

Step 2: turn it into the Tome of Dalaran in Ambermill
Leave Shadowfang Keep and go to Ambermill in Silverpine Forest, the town held by Dalaran. In the keep you find the Ambermill Leyline Focus. Use the Black Tome next to it and it becomes the Tome of Dalaran.

Players found the Black Tome and this step a while ago, but after Ambermill the trail went cold, until the City of Dalaran dungeon came to the beta.
Step 3: summon Lyn in the City of Dalaran
Kill the first boss, Atrexis the Grave Knight, and follow the sewers. Where the path turns right towards the surface, go straight on into the tunnel with a purple rune on the floor. This room used to look like a dead end. Use the Tome of Dalaran there, and after a short scene Lyn appears.

His entrance is a nice wink to Ragnaros: he complains that he is being summoned far too soon.

Good to know
- The Tome of Dalaran is not used up, and has only a 3 minute cooldown. Wipe? Try again right away.
- As Horde you first need the attunement to get into the dungeon. Our guide: https://legendsofazeroth.com/news/how-to-get-attuned-to-the-city-of-dalaran-dungeon-as-horde
What this means for Legends of Azeroth
A secret boss is a fun goal for a guild group. Who wants to try it on the beta, or save the surprise for launch? Plan a run in Discord or on the forum!