Element Master

You have complete control of your elemental specialty, granting you the following benefits: 

• Elemental Mastery.  When you deal your Elemental Affinity's damage type, you gain a bonus to the damage equal to the number of damage dice.
• Elemental Harmony.  When you cast a spell that deals damage, you can change the damage type to your Elemental Affinity. Damage from spells you cast, or that you deal, treat immunity to your Elemental Affinity as resistance.