Would be great if you actually said where the puzzle is from the quest. Went to the page for the quest, and it doesn't say where the puzzle is at either.

in case someone is as fool as me, for 4th book, HIT THE GODDAM WALL!!!, climb the wall above exquisite chest, remember the pattern, go to the shrine in the serpent's heart, and do the pattern, you can't expect me to remember what quests do, there's hundreds of them dammit!!!

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" Mine is currently bugged, I was exploring and completed the mechanism at the Serpent's Heart BEFORE the world quest (and didn't give me the book), and now the chest doesn't reappear anymore. "

same here i hope they fix it :\

Mine is currently bugged, I was exploring and completed the mechanism at the Serpent's Heart BEFORE the world quest (and didn't give me the book), and now the chest doesn't reappear anymore.

after doing the quest follow the seelie in the corner of the library's first floor through the mirror for a chest ;)

You don't need to finish the tricolor file world quest to get the last book. it's there in one of the cages.

Currently it seems that if you had already purchased "The Serpent and Drakes of Tokoyokoku" before 2.4, then the quest will be bugged and will not allow you to finish it.

For those before this post gets updated: you can get the Hydrological Studies In Byakuyakoku by solving the maze east of the northern evernight temple waypoint. Then talk to Date, solve his second maze/puzzle and open the door to his treasury.