Kidney Stone
ItemAfterbirthLocked
passiveGame ID 440★★★★
How do you unlock Kidney Stone?
In The Binding of Isaac, Kidney Stone is unlocked by unlocking Kidney Stone (Achievement).
Structured pathSource-backed requirements are mapped into trackable steps.
Isaac is occasionally forced to stop firing and charge an attack that launches a massive piercing, spectral kidney stone and a barrage of tears. [Before Repentance] -0.2 speed, decreases range.
How to unlock: [before Afterbirth+] Complete The Guardian (challenge #30) / [Afterbirth+] Complete Onan's Streak (challenge #29)
What unlocking Kidney Stone leads to
Nothing depends on this yet.
Source: bindingofisaacrebirth.wiki.gg
Imported 2026-09-13