The book Igor wants is in the cave accessed by the top teleporter. In the third section of that cave, I don't recall exactly (from D2:ED), but the book should be sitting on the ledge along the left wall (if not check the chest).
In the Primordial cave, are there 3 statues in front of the door that you can not open? You can talk to each of the statues...
The chicken rune can be used for a quest.
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