Kidney Stone is an unlockable passive item in The Binding of Isaac, added in the Afterbirth DLC.

Firing tears will occasionally cause Isaac's head to turn read and charge an attack. Releasing the attack will fire a kidney stone that deals 5x Isaac's damage and pierces enemies, followed by a rapid, inaccurate spray of tears.

When the effect is activated, Isaac gains a temporary x6 fire rate multiplier that decreases rapidly.

The effect occurs immediately when the item is acquired, and every ~25 seconds.

Isaac cannot fire tears normally until the kidney stone effect ends.

This page shows the latest information as of the new Repentance+ (Online Co-op) DLC.
To see information about this item for the previous Repentance version, check this page instead.

Complete challenge #29: Onan's Streak.

Kidney Stone can be found in the following item pools:

The following tags are applied to this item:

• Check out the item description on the external Isaac Wiki.