Binding of Isaac: Rebirth Wiki

Book of Secrets is an unlockable activated item.

Effect[ | ]

  • Randomly adds the effect of Collectible Treasure Map iconTreasure Map, Collectible The Compass iconThe Compass, or Collectible Blue Map iconBlue Map for the duration of the current floor.
    • (in Repentance) If all effects are active, Collectible X-Ray Vision iconX-Ray Vision is provided for the floor instead.
  • Repeated activations will continue to add the other items' effects.
    • (except in Repentance) The chosen effect on activation may be one that Isaac already has - effectively doing nothing.
    • (in Repentance) Book of Secrets cannot give mapping effects that Isaac already has (whether from a previous activation or through possessing the equivalent item). After all effects have been given, further activations do nothing.
  • (in Repentance) Highlights any Tinted Rocks and rocks with Crawl SpaceCrawl Space in the room.
  • (in Afterbirth † and Repentance) This item belongs to the BookwormBookworm set. Collecting three items from this set will transform Isaac into Bookworm.

Notes[ | ]

Synergies[ | ]

  • (in Repentance)Collectible Book of Virtues iconBook of Virtues: Spawns wisps in the middle ring, looking like tiny spinning question marks. The wisps invoke the effect of Collectible Cracked Orb iconCracked Orb when destroyed.
  • (except in Rebirth)Collectible Car Battery iconCar Battery:
    • (in Afterbirth and Afterbirth †) Activates twice, but has a chance to uselessly activate the same effect twice.
    • (in Repentance) Gives 2 different mapping effects and extends the duration of the glow effect applied onto special rocks.
  • (in Repentance)Collectible The Mind iconThe Mind: Immediately gives the Collectible X-Ray Vision iconX-Ray Vision effect for the floor upon use.

Gallery[ | ]

Trivia[ | ]

  • This item may be a reference to an Apocryphon, or 'secret book'. This term is used to refer to early Christian writings that were written to teach 'secret knowledge' that wasn't allowed to be publicly taught.
  • Book of Secrets was the first item voted off in a poll to find the worst quality 0 item on r/bindingofisaac, possibly leading to its quality increase in a later update.
  • (except in Repentance) Prior to Repentance, this item's description was "??????"