Rainbow Bean is a trinket in Fiend Folio, a mod for The Binding of Isaac.

Standing near enemies has a chance to expel a random fart.

The chance is calculated once per 0.33 seconds, and scales with luck using the formula random(0, 100) < LuckStat × 2 + 5. With 0 luck, the chance to fart is 5%.

A fart is guaranteed to happen once every 30 failed attempts (10 seconds). However, if Isaac has negative luck, the maximum number of failed attempts is increased by 5 × LuckStat.

A total of 6 different farts can occur:
• 42.47% → Butter Bean
• 30.43% → The Bean
• 13.04% → Kidney Bean
• 13.04% → Linger Bean
• 0.5% → Mega Bean
• 0.5% → Wait What?

The following special synergies and interactions for Rainbow Bean have been documented.

* Note that not all possible synergies and interactions are listed here.

• Check out the trinket description on the mod's external Wiki.
• Download Fiend Folio from the Steam Workshop.