Spirit's Anguish

You purify a spirit by coaxing it to release its anguish in a final cathartic howl. This deals sonic damage to all creatures in a 30-foot cone, with a basic Will save against your class DC or spell DC, whichever is higher. If you expend a spirit wisp, this deals 1d4 per level sonic. If you expend a spirit remnant, this deals 1d6 sonic damage per level of the incorporeal undead or haunt from which you gained the remnant.