From Pathfinder Lost Omens Hellfire Dispatches, which isn't enabled.

Diabolic Certitude

FEAT 4

Activity free action

Trigger Your turn begins, and you can observe a devil.

Your Hellknight training drilled details of Hell's denizens deep into your mind. Attempt a check to Recall Knowledge about a devil you're observing. If you critically fail this check, you fail instead. If you succeed at this check, you critically succeed instead.

Pathfinder Lost Omens Hellfire DispatchesORC