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From Pathfinder Impossible Magic, which isn't enabled.

Detect Anathema Fulu

ITEM 8
Price 100 gp
Usage affixed to armor
Bulk —
Category fulu

Given to undisciplined acolytes at risk of breaking their vows, this fulu activates on its own if its wearer begins to perform an act anathema to a specific deity or cause, decided at the time of crafting. The fulu heats up when activated, giving you enough warning to correct your actions; if you proceed, the fulu immolates in a burst of flame. This deals 4d6 fire damage and brands your skin until you receive an appropriate Atone ritual. Either way, activating the fulu consumes it.

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