Bursting Sack
ItemAfterbirthUnlocked
passiveGame ID 377★★★★
How do you unlock Bursting Sack?
Verified starting unlockSource data confirms that no unlock is required.
Spider enemies no longer target or deal contact damage to Isaac.
Available from the start
No unlock needed — this is available in every new save file.
What unlocking Bursting Sack leads to
Nothing depends on this yet.
Source: bindingofisaacrebirth.wiki.gg
Imported 2026-09-13