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Baldur's Gate 3, influenced by its tabletop origins, is full of puzzles that challenge your critical-thinking skills. One such tricky enigma lies in Balthazar's room in Moonrise Towers, where an initial Perception check suggests the age-old book-pushing mechanism puzzle in the bookshelf.
Don't be fooled, however! The solution isn't really tied to the bookshelf at all, but rather, the rest of the macabre decor in the room. Any rushed attempts to play with the books might lead to death, or worse, stinky zombie surprises. So, before you start clicking around, be sure to read this guide thoroughly to navigate Balthazar's room safely and successfully!
Where Is Balthazar's Room
As you traverse the ominous Moonrise Towers, the story will steer you towards Balthazar's Room, particularly if you're in search of a Moonlantern, which is essential for wandering the shadow-cursed lands safely.
If you didn’t obtain a Moonlantern from Kar'niss or lost its blessing, paying a visit to Balthazar's macabre chambers will be crucial to progress. And even if you don’t need the lantern, the room promises a boon that will cost you nothing—except, perhaps, your morals.
You'll find Balthazar's Room (X:-132, Y:-182) on the First Floor of the Moonrise Towers. It's tucked behind a locked door that requires a key or a successful DC 15 Sleight of Hand check.
If you're playing your cards right and feign allegiance to the Absolute, Disciple Z'rell will hand over the key on her own after you speak to her.
Balthazar's Bookshelf Puzzle: Overview
Here is a quick rundown of how you can solve the puzzle. A more in-depth explanation will follow in the next section.
- Find Balthazar's Room.
- Pass a DC 10 Perception check to see the protruding books in the bookshelf.
- Click on the top-right book, which unlocks the Ancient Altar to the right of the shelf.
- Read the "Attention Acolytes" book on a table to the south.
- Grab the heart from the sacrificial altar in the middle of the room.
- Place the heart into the Ancient Altar.
- The bookshelf should slide open after this.
Balthazar's Bookshelf Puzzle: Full Solution
Starting the Puzzle
The bookshelf puzzle involves the large bookshelf to the west of Balthazar's Room. Walking closer to the bookshelf will prompt an automatic DC 10 Perception Check from your party; upon success, you'll notice four protruding books.
Touch the protruding book on the top-right of the bookshelf. You'll hear a click—this should unlock the small Ancient Altar directly to the right of the bookshelf.
Touching any other book will unleash a deadly trap in the room—ranging from a lightning trap, poisonous fumes, or reanimating all the corpses in the room.
A Beating Heart
Navigate to the west of the room, where you'll see a table with a red book on it named Attention Acolytes.
The text hints that the Absolute is best served by a "beating heart".
After this, you can grab the heart on the altar in the middle of the room and place it into the Ancient Altar that was unlocked in the previous step.
The bookshelf should slide open after this, and you'll be able to enter Balthazar's Moonlantern laboratory, where you'll be able to decide between crafting a buffed Moonlantern or destroying the site altogether.
If you somehow lose the heart on the altar, some of the viscera and corpses on the ground will contain hearts.