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Balthazar's Room in BG3: Bookcase Puzzle, Ancient Altar and Moonlantern Location
Baldur's Gate 3

Balthazar's Room in BG3: Bookcase Puzzle, Ancient Altar and Moonlantern Location

Learn how to solve Balthazar's bookcase puzzle in Baldur's Gate 3, find the Ancient Altar, and locate the Moonlantern in his secret room.

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Learn how to solve Balthazar's bookcase puzzle in Baldur's Gate 3, find the Ancient Altar, and locate the Moonlantern in his secret room.

Walkthrough
  1. 1
    Infiltrate Moonrise Towers: Speak with General Thorm, then head upstairs to speak with Disciple Z'rell.
  2. 2
    Obtain Balthazar's Key: Gain Z'rell's trust in dialogue. She will task you with finding Balthazar and a relic from the Thorm family mausoleum. She will then give you a key to Balthazar's room.
  3. 3
    Alternative Entry: You can attempt to lockpick Balthazar's door, but be aware of nearby guards.
  4. 4
    Solve the Bookcase Puzzle: Enter Balthazar's room. On the left wall is a bookcase with 'Protruding Books'. Interacting with the upper right set of books will reveal an Ancient Altar next to the bookshelf. Interacting with other books may reanimate corpses or trigger damaging spikes.
  5. 5
    Use the Ancient Altar: Interact with the Ancient Altar. You will need to place a heart (found nearby) into the altar.
  6. 6
    Discover the Secret Room: Placing a heart on the altar opens a hidden passageway behind the bookcase.
  7. 7
    Gale's Interaction: If you have Gale in your party, he will have a unique interaction when you enter the secret necromancy room. Interact with the Ritual Circle inside.
  8. 8
    Moonlantern Transformation: Gale can offer to transform the broken Moonlantern into a Shadowlantern. You can choose to let him, tell him to craft the Shadowlantern, tell him to destroy it, or attempt to destroy it yourself (requires a DC30 check).
  9. 9
    Obtain the Moonlantern: Balthazar's Moonlantern is located next to a wooden desk near a telescope.
Tips
  • A normal torch can provide light in the Shadowlands, but the Moonlantern has a much larger area of effect, keeping your entire party safe.
  • If Gale destroys the Moonlantern, Mystra will be pleased and grant him a permanent buff: advantage on Concentration checks.
  • If you already possess a Moonlantern, you do not need to pick up Balthazar's, but it can serve as a spare.
  • Balthazar's Moonlantern (or Shadowlantern if transformed).
  • If Gale destroys the Moonlantern, he receives a permanent buff: advantage on Concentration checks.

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