Contagion
ItemAfterbirth+Unlocked
passiveGame ID 466★★★★
How do you unlock Contagion?
Verified starting unlockSource data confirms that no unlock is required.
The first enemy killed in a room releases a gas cloud that poisons nearby enemies. Affected enemies will also release gas upon death, spreading the effect.
Available from the start
No unlock needed — this is available in every new save file.
What unlocking Contagion leads to
Nothing depends on this yet.
Source: bindingofisaacrebirth.wiki.gg
Imported 2026-09-13