Black Heart (half) (woah no way half black heart) is a pickup in Lazy MattPack, a mod for The Binding of Isaac.

Does not spawn naturally, and can only be found while holding a partially depleted Kitchen Knife.

Adds a half black heart.

When depleted, black hearts activate The Necronomicon effect, dealing 40 damage to all enemies in the room.

• Download Lazy MattPack from the Steam Workshop.