|Guppy||Beelzebub||Super Bum||Yes Mother?||Bob||Fun Guy||Leviathan||Conjoined|
|Spun||Seraphim||Oh Crap||Bookworm||Spider Baby||Adult||Stompy|
Isaac turns into his cat Guppy after picking up any 3 distinct items from this item pool. As Guppy, Isaac gains flight.
When Isaac or one of his familiars hits an enemy with a tear, a Blue Fly spawns.
Blue Flies have a 50% chance to spawn when Isaac or one of his familiars hits an enemy with a tear.
Laser attacks from Brimstone, Technology, Tech X and Urn of Souls also work normally, but Mom's Knife and Technology 2 spawn flies only very rarely. Explosions and non-tear based attacks from familiars do not spawn flies.
|Guppy's Head||5.100.145||Reusable fly hive||Spawns 2-4 friendly Blue Flies that damage enemies.||3|
|Guppy's Paw||5.100.133||Soul converter||Upon use, converts one Red Heart Container into three Soul Hearts.||3|
|Dead Cat||5.100.81||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||Eternal life?||Grants a permanent 50% chance to respawn with 1/2 of a Red Heart after death.||2|
|Guppy's Hair Ball||5.100.187||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||Cursed?||Room Clear Awards have a 1/3 chance of being replaced with a Chest and a 1/3 chance being replaced with nothing.||2|
|Guppy's Eye||5.100.665||An eye for secrets||Shows the contents of Chests, Sacks, and Fire Places before they're opened/bombed.||2|
|Kid's Drawing||5.350.169||Looks familiar...||While held, counts towards the Guppy transformation.|
- If all the 9 extra lives have been consumed, Dead Cat is considered lost. This may even cause the transformation to be removed.
- Duplicates items still count separately towards the transformation.
- This transformation is a reference to Edmund's first cat, as seen in some of his early videos on his personal channel.
- In the original Binding of Isaac, this transformation was called "Cursed?"
- Transforming into Guppy as The Forgotten will give him apperance of a cat's skeleton.
PC XWN6 1YWH (The Basement I - Curse Room above spawn contains 2 Red Chests and Bomb Chest, Guppy's Collar, Guppy's Head and Dead Cat respectively)
PC 7TC3 43F1 (The Cellar I - Curse Room above spawn contains 2 Red Chests and Bomb Chest, Guppy's Collar, Guppy's Paw and Guppy's Head respectively
|The Binding of Isaac: Rebirth|
|Achievements||Attributes||Bosses||Cards and Runes||Challenges||Chapters|