The Book of Belial

3  rooms

Devil Room Library Devil Room Library Treasure Room

(page 1, column 14, row 2)(page 1, column 4, row 4)

Not to be confused with Satanic BibleUpon activation, Isaac gains a black heart..

The Book of Belial is an activated item.

Effect

• Increases damage by 2 upon use for the current room.
• Guarantees the Devil Room or Angel Room to spawn after killing a boss while holding it.
  • Increases the chance to open the Devil Room or Angel Room by 12.5% after killing a boss while holding it instead.

Notes

• Judas starts with this item by default.
• The x1.5 damage multiplier does not stack with the x1.5 damage multiplier from Cricket's HeadIncreases damage by 0.5, and multiplies it by 1.5x. or Magic MushroomIncreases all stats and enlargens Isaac..
• The Book of Belial cannot open Devil Rooms in The Basement I / The Cellar I, nor in Chapter 5 and beyond, even though they can reached by other means (through the JokerTeleports you to the Devil Room or Angel Room. playing card, for example).
• Unlike Goat HeadA Devil Room / Angel Room Door will always spawn after every boss fight, excluding the first floor and floors after Utero II/Womb II., picking up The Book of Belial after killing the boss won't open the Devil/Angel Room Door.
  • The Book of Belial increases the chance of a Devil/Angel Room Door to spawn, while Goat HeadA Devil Room / Angel Room Door will always spawn after every boss fight, excluding the first floor and floors after Utero II/Womb II. forces open a door to said rooms permanently.
• The damage bonus does not stack with multiple uses in a room, or with the tarot card XV - The Devil, which has the same effect.
• Switching items breaks the bonus damage effect.

Synergies

• Blood of the MartyrIncreases Damage by 1, and turns Isaac's tears into blood tears.: Causes The Book of Belial to apply a 1.5x damage multiplier on top of its normal effect.

Gallery

• 

  Book of Belial when activated.

• 

  Unused image for use animation. This sprite was used in the original game's "Wrath of the Lamb" DLC.

• 

   3DS  The Icon of the Book of Belial as seen on the lower 3DS screen.

Trivia

• Can still open Angel Rooms even though it is a satanic book.
• It is one of the four books in the Satanic Bible.
• Belial is a name used for Satan in some Jewish and Christian texts.

Seeds

 PC  ZWQY MQ6C

 Switch  ZWC9 D2WY

Book Items

• Anarchist CookbookSpawns six troll bombs around the room.
• The BibleUpon activation, Isaac gains flight, allowing him to pass over all obstacles in the current room. Instantly kills Mom, Mom's Heart, and It Lives when activated, but will kill Isaac when activated while fighting Satan.
• The Book of BelialUpon use increases damage by 2 for the current room and by a further +50% if the character also has the Blood of the Martyr.
  Guarantees a Devil Room or Angel Room will be open after beating a boss while holding it, or increases the chance by 12.5%.
• Book of the DeadUpon use, spawns a friendly Bony or an orbital bone for each enemy killed in the current room.
• Book of RevelationsAdds 1 soul heart, increases the chance for a Devil or Angel Room to appear, and increases the chance for the next boss to be a Horseman (except on XL floors and floors with fixed bosses such as Mom).
• Book of SecretsUpon use, gives the effect of Treasure Map, The Compass, or Blue Map for the duration of the current floor.
• Book of ShadowsUpon use, creates a protective shield nullifying all types of damage for 10 seconds.
• The Book of SinSpawns a random pickup, pill, card, or trinket.
• How to JumpGives Isaac the ability to jump (over gaps, spikes, etc.).
• Monster ManualSummons a random familiar for the current room. Can summon familiars not yet unlocked.
• The NecronomiconDamages all enemies in the room significantly.
• Satanic BibleUpon activation, Isaac gains a black heart.
• Telepathy for DummiesUpon activation, grants homing tears for the current room.