Binding of Isaac: Rebirth Wiki
Character Isaac appearance.png
Full red heartFull red heartFull red heart
Table dividing line 1.png
Challenge Number
Available Rooms
Item Pool Treasure Room.png: no          Item Pool Shop.png: yes
Boss Mom's Heart portrait.png
Unlock Method

Purist Defeat Mom

Purist is challenge #20. This challenge is unique because Isaac starts with no items. The goal is to defeat Mom's Heart Mom's Heart or It Lives It Lives. This Challenge is unlocked after defeating Mom Mom for the first time.


Because there are no Treasure Room Treasure Rooms, it is harder to find items. While this is standard for most challenges, Isaac also doesn't start with any items.


  • Other special rooms become much more important, with Devil Room Devil Rooms and Angel Room Angel Rooms becoming even more valuable than on an average run.
  • Cards such as Credit Card Credit Card and items such as Added in AfterbirthDiplopia Diplopia, Added in Afterbirth †Coupon Coupon and Added in Afterbirth †Mr. ME! Mr. ME! can be used for the Shop Shop and Devil Room items, with Diplopia cloning the items, and Credit Card/Coupon allowing the item(s) to be taken for free. Neither option stops Angel Rooms from appearing.
  • Bomb Bombs are much more valuable when hunting for Secret Room Secret Rooms as these can provide free items.
  • Removed in Repentance Curse Room Curse Rooms guarantee damage and can lower the chances of Devil Rooms. However, if Isaac has a full Soul Heart Soul Heart, Black Heart Black Heart, or Added in Afterbirth † Bone Heart Bone Heart, the reward can outweigh the damage and still allow Isaac to access a Devil Room. Alternatively, wait to enter the Curse Room until after visiting the Devil Room.
  • The Bible The Bible can be used to instantly win the boss fights against Mom Mom, which can be used to preserve key health, and Mom's Heart Mom's Heart/ It Lives It Lives, which will complete the challenge.