"Danier and I explored the dungeon last night -- many, many broken dolls, rifts and twists and turns later, we had navigated this LONG dungeon.  It's hard to get lost in it -- there are really no dead ends, just a few squares with one way in and one way out.  

 

Tonight Dirrich the Warden was spawning in the basement. I waited my turn and burned him!  He rewarded me with some odd gauntlets.... I have this funny feeling I cannot set them down. I also have an obsidian shard I'm going to take to have translated ASAP."

When you first try to enter the portal, you will receive the following message:
You have not completed the quest required to use this portal.

To enter, you must first kill Narrow and Shallow Rifts outside the portal until you get this message which will trigger the quest:

You feel the energy released by the rift's destruction enter you. You feel changed..."

You are now flagged to enter the dungeon. As Doogen mentions, the dungeon is straightforward, if quite long. You'll encounter Broken and Battered Dolls and Narrow Rifts inside. You'll have to jump over a pit to reach the end where Dirrich the Warden -- a level 45 Virindi -- awaits (approx. 3 minutes spawn). Kill him for your reward: the Shackles of Obedience and an Obsidian Shard.

Dirrich, the Warden is incinerated by your assault!
A flash of violet backlights the Virindi's mask, and in your mind, a hollow voice intones, "So this is my reward for following the Directive. Arabax was right..."

Text: Dirrich's Journal

The Obsidian Shard can be translated by Diyas al-Yat in Zaikhal.

You give Diyas al-Yat Obsidian Shard.
Diyas al-Yat tells you, "This really provides some insight into the inner workings of the impure Virindi. It is such a pity to see broken dolls where there was once such purity. Pity."

The Shackles of Obedience are a pair of bracers that cannot be given away. Not even to a Town Crier! They can, however, be destroyed by using a mana stone on them. The Obsidian Shards may be dropped or given away.