Go to Orphiel's Tower in Meridian, and take the elevator to the second floor. On the ground, you will see two crazed librarians surrounding a book. Collect the book, when you do so you will receive a 'buff' called Abyssal Madness (lasts 1 hour) which allows you to see the below apparitions around Meridian and Shoreward Island.
You will find Alyete Bathsube behind you on the other side of the room. Speak to her.
You will need to talk to Eddie. Eddie is located on Shoreward Island (north of Freemarch and east of Silverwood). Swim directly from the northern-most peninsula in Freemarch and swim directly to the island. You are able to make it in a straight shot without dying as the water around the island does not cause fatigue. If you swim near the ocean floor you'll notice two broken boats, you only take fatigue while in between them so they can be helpful markers. Go left along the shore to find Eddie.
See our video walkthrough to finding Eddie, below.
Return to the second floor of Orphiel's Tower in Meridian, where you found the book. Use the quest item Eddie gave you to bind the Forbidden Tome (this will automatically remove Abyssal Madness). Return to Faceless Man to complete the quest.
The information contained on this page is related to the Defiant version of the Water Saga.