Binding of Isaac: Rebirth Wiki

Book of Secrets is an unlockable activated item.


  • Randomly adds the effect of Treasure Map Treasure Map, The Compass The Compass, or Blue Map Blue Map for the duration of the current floor.
    • Added in Repentance If all effects are active, X-Ray Vision X-Ray Vision is provided for the floor instead.
  • Repeated activations will continue to add the other items' effects.
    • Removed in Repentance The chosen effect on activation may be one that Isaac already has - effectively doing nothing.
    • Added 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.
  • Added in Repentance Highlights any Tinted Rocks and rocks with Crawl Space Crawl Space in the room.
  • Added in Afterbirth † This item belongs to the Bookworm set. Collecting three items from this set will transform Isaac into Bookworm.



  • Added in RepentanceBook of Virtues Book of Virtues: Spawns wisps in the middle ring, looking like tiny spinning question marks. The wisps invoke the effect of Cracked Orb Cracked Orb when destroyed.
  • Added in RepentanceCar Battery Car Battery: Gives 2 different mapping effects and extends the duration of the glow effect applied onto special rocks.
  • Added in RepentanceThe Mind The Mind: Immediately gives the X-Ray Vision X-Ray Vision effect for the floor upon use.



  • 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.
  • Removed in Repentance Prior to Repentance, this item's description was "??????"


PC ANVY YAPC (First floor Library Library)

PS4 2YVW FZ34 (Treasure Room Treasure Room adjacent to spawn)

Vita FHQG 1L9Y (First floor Treasure Room Treasure Room)