When the collection is complete, you can turn it in to any Collector NPC for your reward and a very nice chunk of experience.

Items in this Collection

1. Head to the Commonlands into Zarvonn's Tower and examine the large, brown book on a table on the second floor of the tower. This is The Binder to the Lore of Fauna: The Behemoth which you must examine to start the collection. Then add the book itself to the collection.
2. Harvestable pages will now be visible to you (with ! over them) in Zarvonn's Tower in the Commonlands and back inside The Eternal Gorge. Harvest all 13 pages to the book:
• Pages 2 through 10 are in Zarvonn's Valley: Eternal Gorge.
• These spawn randomly in the buildings, near walls, next to rocks, and inside the tower itself in the gorge. They respawn in a short period of time, but you can speed up the process by zoning out and back in again to reset the zone.
• Page 11 is on the 4th floor of Zarvonn's Tower
• Page 12 is on the 3rd floor of Zarvonn's Tower
• Page 13 is on the 2nd floor of Zarvonn's Tower
• Page 14 is on the ground floor of Zarvonn's Tower
3. Speak with any collector for your reward.