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The Library is a room added 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 start the floor with a book in your spacebar slot.

NotesEdit

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.
Picking up a Book with The Dice and then picking up The Dice again will allow you you to re-roll the book into other items instead of other books.
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 LibraryEdit

Item	Icon	Effect
Anarchist Cookbook		Spawns six troll bombs around the room.
The Book Of Belial		Doubles damage until you exit the room.
Book Of Revelations		Adds 1 Soul Heart and makes the next boss a horseman if possible.
Book Of Shadows		Grants invulnerability for a short time.
The Book Of Sin		Spawns a random Pick Up, Pill or Card.
Monster Manuel		Summons a random familiar for the current room only.
The Necronomicon		Damages all enemies in the room significantly.
Telepathy For Dummies		Tears track targets for one room.