You can channel chthonic akasha to enhance your precision-based damage.
Prerequisites
Constitution 13 or veilweaver level 1, and one or more of the following class features: sneak attack or other precision damage ability.
Benefit
You can bind essence into this feat. Once essence is bound, it remains invested for 24 hours or until the next time you weave veils for the day.
You gain an insight bonus equal to twice the invested essence on all damage rolls when dealing a sneak attack or other precision damage. This is considered precision damage and is not multiplied on a critical hit.
You gain 1 point of essence.