Boss Challenge Room is a room in The Binding of Isaac.

The Boss Challenge Room features 2 waves of bosses in exchange for a reward.

The room will only generate on a floor if Isaac has full health upon entering the floor, but the room may only be entered if he has one or fewer total hearts.

Boss Challenge Rooms appear only on the second floor of a chapter, and may appear up to Chapter 5. Only one Boss Challenge Room may generate per floor.

The room contains one item from the item pool that, when interacted with, initiates the boss waves.

The bosses inside the room depend on the current chapter.

Each completed wave will grant 1 charge to Isaac's active item and will trigger other room-clear effects such as familiars that spawn stuff based on the number of cleared rooms.

Completing both waves will yield a regular room clear reward.

If Isaac teleports out of the room after it has been initiated, returning to the room will not continue the challenge unless another item pedestal is present inside the room, or a chest is opened.

This page shows the latest information as of the new Repentance+ (Online Co-op) DLC.
To see information about this room for the previous Repentance version, check this page instead.

The Boss Challenge Room is associated with the Boss item pool. Items that spawn in this room will be selected from the associated item pool.

• Check out the room description on the external Isaac Wiki.