Shattering Strike (Weapon Improviser)

Trigger An improvised weapon that you are wielding becomes broken as a result of a critical success on an Improvised Pummel. The improvised weapon shatters, destroying it completely but dealing an additional 3d6[piercing] damage to the creature you hit with the Improvised Pummel. This extra damage you apply on the critical hit doesn't double from the critical hit, as normal.