Chaotic Evil alignment or completed Phase 2 from Chapter 7: Drawbacks of Evil
The character can transform one of her spells into thing of evil due to a deal she makes with an evil power.
Benefit:
This feat adds the evil descriptor to a spell. Furthermore, if the spell deals damage, half of the damage is unholy.
You must choose the spell at the same time you receive this dark gift.
Special:
A character may take this multiple times, choosing a different spell each time.