Binding of Isaac: Rebirth Wiki

After picking up 3 items from the following list Isaac turns into his cat Guppy.

(except in Repentance) As Guppy, Isaac gains flight, and when one of his tears or one of his familiar's tears hit an enemy, a Blue Fly spawns.

(in Repentance) As Guppy, Isaac gains flight, and when one of his tears hit an enemy, there is a 66% chance to spawn a Blue Fly.

Activated Collectibles[ | ]

Name ID Icon Quote Description (in Repentance) Quality
Guppy's Head 5.100.145
Guppy's Head
1 room
Reusable fly hive Spawns 2-4 friendly Blue Flies that damage enemies. 2
Guppy's Paw 5.100.133
Guppy's Paw
Soul converter Upon use, converts one Red Heart Container into three Soul HeartSoul Hearts. 3

Passive Collectibles[ | ]

Name ID Icon Quote Description (in Repentance) Quality
Dead Cat 5.100.81 Dead Cat 9 lives Sets Isaac's Red Heart Containers to 1, but grants 9 extra lives. After dying, Isaac respawns with 1 Red Heart Container. 3
Guppy's Collar 5.100.212 Guppy's Collar Eternal life? Grants a permanent 50% chance to respawn with 1/2 of a Red HeartRed Heart after death. 1
Guppy's Hairball 5.100.187 Guppy's Hairball Swing it Spawns a familiar that loosely follows behind Isaac, which blocks shots can be swung like a flail to damage enemies. Grows bigger by killing enemies. 1
Guppy's Tail 5.100.134 Guppy's Tail Cursed? Room Clear Awards have a 1/3 chance of being replaced with a ChestChest and a 2/9 chance being replaced with nothing. 2
(in Repentance) Guppy's Eye 5.100.665 Guppy's Eye An eye for secrets Shows the contents of ChestChests, Fire PlaceFire Places, Grab BagGrab Bags, and ShopkeeperShopkeepers before they're opened/destroyed. 2

Trinkets[ | ]

Name ID Icon Quote Description
(in Repentance) Kid's Drawing 5.350.169 Kid's Drawing Looks familiar... While held, counts as one of three items needed to transform into GuppyGuppy.

Notes[ | ]

  • Collectible Technology 2 iconTechnology 2 spawns flies only very rarely.
  • (except in Afterbirth †)If Isaac has transformed into Guppy, Guppy's Hairball spawns Blue Flies when it deals damage.
  • (in Repentance) If all the 9 extra lives have been consumed, Collectible Dead Cat iconDead Cat is removed from Isaac's inventory. This causes the transformation to be removed.

Unlockable Achievements[ | ]

Trivia[ | ]

  • This transformation is a reference to Edmund's first cat, as seen in some of his early videos on his personal channel.[1]
    • Guppy the cat passed away in 2014.[2]
  • (in Afterbirth † and Repentance) Transforming into Guppy as Character The Forgotten iconThe Forgotten will give him the appearance of a cat's skeleton.
  • (in Repentance) The guppy item tag determines if an item counts towards the transformation, except for Kid's DrawingKid's Drawing which seems to be hard-coded to count as a Guppy item despite not having the tag.

References[ | ]