Key Bum

Item Icon
Pickup Quote	"He wants your keys!"
Entity ID	5.100.388
Item Pool	Baby Shop Key Master Secret Room Treasure Room
Quality	0
Item Tags
Collection Grid	(page 4, column 3, row 2) (page 4, column 3, row 2) (page 4, column 4, row 2)
Unlock Method	Defeat Ultra Greed as Lazarus

Key Bum is an unlockable passive item added in The Binding of Isaac: Afterbirth.

Effects

• Spawns a familiar that follows Isaac around and collects Keys, dropping random Chests in return. (He does not fill up a familiar "slot".)
• This item belongs to the Super Bum set. Collecting three items from this set will transform Isaac's bums into Super Bum.

Notes

• Key Bum will not pick up Golden Keys.
• Key Bum will pick up Charged Key without additional benefit.
  • Key Bum will leave a Lil' Battery behind when picking up Charged Key.
  • From a scoring perspective, Keys that Key Bum picks up count towards your Schwag bonus on daily runs. (only applies to Afterbirth and Afterbirth ✞ dailies)

Synergies

• BFFS!: Familiar is bigger and drops chests more often.
• Flat Penny: Chests frequently contain pennies, which have a chance of spawning more keys for Key Bum to pick up, possibly lead to a loop.
• Gilded Key / The Left Hand: Works as expected.
• Guppy's Eye: Allows Isaac to choose which Locked Chests are worth opening and which to pass, thus saving keys. Great for min-maxing.

Trivia

• This item is the Key Master counterpart of Bum Friend and Dark Bum

Seeds

PC WJK1 9R0Z (Treasure Room adjacent to spawn)

Bugs

Bug!	If Credit Card is used in a Shop with Keys, Key Bum will not be able to pick up the free keys. This can be fixed if Isaac leaves and re-enters the shop.

Bug!	Charged Keys do not increment Key Bum's key count when picked up.

The Binding of Isaac: Rebirth
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