Barbed Quills

You break off quills in your attacker's flesh. You deal 1d8 per 2 levels (rounded up) piercing damage to the triggering creature (basic Reflex save using your class DC or spell DC, whichever is higher.) On a critical failure, the creature also takes 1d4 + (your level ÷ 2, rounded up) − 1 bleed as your quills hook into its flesh. At 3rd level, and every 2 levels thereafter, this damage increases by 1d8 and the persistent piercing damage increases by 1.