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Queen's Domain: Library Books
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A short guide to the books needed for the tower storage + The Record of Sin books.
Steam Community guide by Mightythorn.
The Great Works IV - Rubedo
In this cliff below the Cemetery on the starting Island, you will find the entrance to a cave with a egg outside it.
Once you enter and reach the bottom of the stairs inside, the book will be on a Altar to the right of the throwing item in the center of the room. You can reach it by using your air dashes from the stairs or on top of the pedestal where the throwing weapon was
Upim's Fairy Tales
Starting from just outside the entrance ramp to Obmuer temple, using 3 air dashes from the right to the left will get you to the entrance of the second books location. Its very dark and the enemies are tough for when you can reach it, but by continuing downwards you will eventually reach this room
Dropping down the hole, you immediately want to air dash onto the ledges near the top. If you fall too far you will have to use a Crystal or stone fragment to try again
Once you are on the ledge, circle around till you see a food item and a skeleton, the book will be right next to it
The remaining books inside the library

2 of the books are within this room, Koko's Sapphic Adventure and The History of Dragons. The Dragon book is given to you by Woura after you catalogue enough enemies.

The book Dams and Weirs is in this bookcase next to the teleporter on the bottom shelf.
The Old Ones Beyond is through a secret wall above the entrance in this room. Inside will be a skeleton holding the book which drops it on death
Returning the books
Once all books have been acquired, all that is left for the treasure is to slot them in. The order is The Great Work IV - Rubedo, The History of Dragons, Dams and Weirs, Upim's Fairy Tales, The Old Ones Beyond, Koko's Sapphic Adventures
But wait, there's more! - Wodaso's Embrace
Upon claiming the lance from the statue, looking to your right you'll notice there's a new book called Wodaso's Embrace. This is part of a another set of books I'll refer to as God books.
The Rotting God
The next book of this set is back in Obmuer temple past the gap depicted above. Keep going till you reach the dark area
At the far end of the first room, there is this skeleton pointing above. You can reach this ledge either from jumping on the bit of stone above him, or going a bit further and dashing from the ledge with the archer skeletons back towards the way you came. Once you reach it, you'll open a secret door like pictured.
Drop down the hole within, sticking to the leftmost path. You'll encounter some skeletons and not far past a group of Crawlers. The book 'The Rotting God' which talks about Yubior the avatar of Jigeki will be on a stone right next to this group
Monarch of the Void
Head back into this room, after clearing the heads in the pitfall, go up to the top secret door.
This time we'll go all the way through, dropping down into the pit.
Right next to where you drop down will be this split corridor, the right side blocked by a gate that you can open. Directly behind you facing this way is the last head to clear the meat from the basement, after doing that head down the left passage.
Going down, you'll see this gate, pass through till you reach the room with all the statues and head to your left.
There will be a skeleton against the pillar, directly in front of him will be the secret passage down to the book
Dash across this room to the window, and there will be the book Monarch of the Void which is about Siraatsu, avatar of Sipeha
The Green Goddess
Starting from Chef Gogi's room, head down the hall immediately to the left of his door till you reach the spiral staircase room
Head up one flight of stairs till you reach these blue torches, against the wall is a secret door that leads into Verdant Hollow
Once you reach here, go towards the giant pillar in the middle of the room and dash to the statue.
From there, dash again across the room towards the second Josami Warden.
On the stone next to them will be the book 'The Green Goddess' about Ruunen, the avatar of Puwema.
Reaching Record of Sin
Once you've acquired all the god books, head over to the lab in Ancient World and circle around to its back
Drop down and head to the gates of the castle
Head to the right of the gate
Up the metal building here
At the top, keep going right
Cross this gap with 5 dashes
Then along this edge
Once you reach the hole, pass it and keep going forward
You'll see this campfire and skeleton looking across a gap. You can make this with another 5 dashes.
On the other side will be the entrance to the Record of Sin where the God Books will be put in
Slotting in the books
Once you leap down you will be facing this direction. Going forward will reach the save of this floor
The doorway in this screenshot will be locked for you till you get the orbs for the tree. Go back the way you came
Right is a dead end with some loot, take the left path
The orbs for the tree will be in the dark area past here
Once you've aquired them, head back to the tree and put them in, this will open the door. Inside, head up two floors via the elevators
The cage room where you will put the books is to the left once you reach that floor. The order of the books going left to right is The Green Goddess, The Rotting God, Wodaso's Embrace, Monarch of the Void. Keep in mind that the actual reward however is not available till you reach the top of the tower and beat the boss.