The Library is a room introduced in the Wrath of the Lamb. It can appear on any floor. It contains two books, chosen at random. The room around you contains bookshelves, and the floor is similar to that of the Cellar's. It can contain any book in the entire game except The Bible.
The Library has a 5% chance of spawning, and a 25% chance of spawning if you have touched a book that is part of the pool in the run.
- The Library can contain two of the same book; the charge of each will be equal and linked; that is, using one will use up the other's charge as well.
- From outside, the Library's door is identical to that of the Shop's, making the two impossible to distinguish when under the Curse of Darkness.
- Because picking up an item means it cannot ever be seen again in the same run, picking up every book that can be found in the Library will force the Library to spawn standard Treasure Room items. This can be easily abused with a combination of The Dice and the Habit.
- The Library will not spawn the The Book Of Belial if you play as Judas. Holding the Book of Belial as Judas does not provide an increased chance of finding a Library.
- The Library will not spawn The Monster Manuel until it is unlocked.
- Despite being a book, The Bible is not part of the normal Library item pool.
List of Books in The Library
Spawns six troll bombs around the room.
|The Book Of Belial|
|Book Of Revelations|
|Book Of Shadows||
Grants Isaac invulnerability for 10 seconds.
|The Book Of Sin|
Summons a random familiar for the current room only, even if it is locked.
Damages all enemies in the room significantly.
Gives Isaac homing tears for the current room. (Identical to Spoon Bender)
- The Library's background music was also used for Ending 13.