From Pathfinder Lost Omens Cheliax, Infernal Inheritance, which isn't enabled.

Fine Print

FEAT 8

Activity free action

Frequency oncer per 10 minutes

Trigger You Strike and deal damage to an Off-Guard creature with your contract blade.

The text of the contracts written across your papery blade contain hidden clauses that can cause great pain for an unsuspecting foe. You deal an additional 2d4 precision damage to the off-guard creature.

Pathfinder Lost Omens Cheliax, Infernal InheritanceORC