Elemental Mastery

You have mastered the power of a specific element, and use your mastery to weave it into your spells. When you gain this feat, you gain the following benefits:

• When you gain this feat, choose one of the following damage types: acid, cold, fire, lightning, or thunder.
• When you cast a spell that deals damage that is not the chosen type, while still being on the list, you can change that spells damage type to the chosen type.