Guppy's Collar is a passive item.
- Grants a permanent 50% chance to resurrect on death.
- This item belongs to the Guppy set. Collecting three items from this set will transform Isaac into Guppy.
- Resurrection items activate in a set order. Guppy's Collar is 6th in this order after Soul of Lazarus, 1up!, Lazarus' extra life, Dead Cat, and Inner Child.
- It is possible to obtain two collars by finding one in a Red Chest, without picking it up, and then finding another collar in a different Red Chest. However, this does not have any additional effects and does not count towards transforming into Guppy.
- Obtaining multiple copies of Guppy's Collar now grants extra lives, depending on how many copies are obtained (obtaining a second collar displays the lives count as '2?', and so on). The chance for Guppy's Collar to activate is defined with separate rolls, but increases the odds for one of the collars to revive Isaac. Additional collars also count towards the Guppy transformation.
- Resurrecting in a Curse Room may trap Isaac if he has no way of recovering health or exiting them without losing health.
- Resurrecting via Guppy's Collar during a Daily Run will count as a death, even if the run is eventually completed.
- This item is a tribute to Edmund's cat Guppy. 
- This item may also be a reference to the Schrödinger's Cat thought experiment.
PC RWBY 10FQ (Curse Room adjacent to spawn, in Red Chest)
PC 1CMD B881 (Curse Room adjacent to spawn, surrounded by Spiders)
PC FM7Z 4VAJ (Curse Room adjacent to spawn, surrounded by Spiders)
PS4 FQTL 13FX (Curse Room adjacent to spawn)
Switch XSDE HE2L (First floor Curse Room)
|Bug!||When the Keeper is resurrected by Guppy's Collar, there is a chance it spawns with half a Soul Heart as health. When a health upgrade is obtained, the Keeper will have 1 coin, as well as the half Soul Heart as health. When a second health upgrade is obtained, the Keeper will lose the half Soul Heart and have 2 coins as health.|
|Bug!||Guppy's Collar can be exploited to gain infinite lives. When Isaac's last will is on the screen, close the game, re-open it, and continue the run. Isaac will appear to die again, and will also have a separate chance to be resurrected.|
- Dead Cat
- Guppy's Collar
- Guppy's Eye
- Guppy's Hair Ball
- Guppy's Head
- Guppy's Paw
- Guppy's Tail
- Kid's Drawing
|The Binding of Isaac: Rebirth|
|Achievements||Attributes||Bosses||Cards and Runes||Challenges||Chapters|