Side Quest: Unfathomable Depths

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You'll receive this quest from From-Deepest-Fathoms at the Riften docks.


From-Deepest-Fathoms will hand you a Lexicon and implore you to return it to Avanchnzel, but she won't tell you what the Lexicon is or how she got it or really much of anything. You'll find Avanchnzel located to the west of Riften. Inside you'll encounter various dwarven automatons, and from time to time you'll witness scenes of the past where a group of adventurers (including From-Deepest-Fathoms) will enter Avanchnzel and steal the Lexicon.

Eventually, you'll make your way to the Boilery, where you'll find the Lexicon Receptacle (#8). A dwarven centurion will be guarding it. If you have trouble with the centurion, then you can lure it back to the nearby trapped hallway (#6), and the traps will make short work of it. When you place the Lexicon in the receptacle, you'll gain Ancient Knowledge, which will increase the armor rating you receive from dwarven armor by 25% and also increase the experience you gain when Smithing by 15%.

1 - Central Chamber

This chamber will allow you to access the different levels of Avanchnzel. The first time you enter the chamber, heading south will take you down to the Animoncultory (Exit A). Heading east will take you up to the Boilery (Exit C), but you won't be able to enter it yet.

2 - Barred Door

You'll only be able to open this door when you exit from the Boilery (via Exit C).

3 - Abandoned Camp

4 - Book

On the table here you'll find the book Racial Phylogeny, which will increase your Restoration skill by 1.

5 - Drennen's Corpse

6 - Traps

The pressure plates on the southern end of the hallway will turn on the traps. The lever on the northern end of the hallway will turn off the traps.

7 - Watches-the-Roots' Corpse

8 - Lexicon Receptacle / Centurion / Breya's Corpse

  1. Doorway between Avanchnzel and the Animoncultory.
  2. Doorway between the Animoncultory and the Boilery.
  3. Elevator between Avanchnzel and the Boilery.
  4. Balcony. If you go through this (world) exit, you'll find a locked chest on your right.
  5. World exit.




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