Completing this transformation will take the three bums and replace them with the Super Bum familiar, who automatically collects all coins, red hearts, and keys in the room and drops twice as many rewards as the regular bums would have produced.
||A portable beggar who follows Isaac, picks up coins for himself, and occasionally drops a pickup after collecting a coin. Does not spawn collectibles.
||He wants to take your life
||Spawns a familiar that follows Isaac around and collects red hearts. For every one-and-a-half red hearts collected, Dark Bum will generate one soul heart, one hostile Spider or one friendly blue spider.
| Key Bum
||He wants your keys!
||Spawns a portable key master that follows Isaac and collects keys, giving random chests in return.
- This transformation has a unique animation sequence when the third bum is picked up.
- When Dark Bum is obtained through Cambion ConceptionAfter taking damage a certain amount of times, a permanent demonic familiar spawns., it does not count towards the transformation.
- If multiple bums of the same kind were present before the transformation, e.g. via Box of FriendsUpon use, duplicates all of Isaac's familiars for the current room., all of them will be replaced with only one Super Bum when three different bums are obtained.
- If any additional bums are obtained after the transformation, they will not be displayed on the screen.
- This is the only transformation that does not affect Isaac himself, but instead transforms (and even fuses) certain familiars.