The Book of Belial

+2 damage for the current room. Guarantees a Devil Room or Angel Room will be open after beating a boss while holding it. Increases the chance by 12.5%.

Quote

"Temporary DMG up"

Effects

• Gives +2 damage for the current room.
• Increases the chance to open the Devil Room or Angel Room by 12.5%.
• This item belongs to the Bookworm set. Collecting three items from this set will transform Isaac into Bookworm.

Synergies

• Blood of the Martyr - Causes The Book of Belial to apply a 1.5x damage multiplier on top of its normal effect. This multiplier cannot stack with multipliers from Cricket's Head or Magic Mushroom.

Found in

• Devil Room
• Library
• Devil Room (Greed Mode)
• Library (Greed Mode)
• Treasure Room (Greed Mode)