When you cast an attack spell, you may choose to lose your mage armor's current resistance and replace it with resistance to that spell's damage types.
While your mage armor is granting you resistance to an arcane damage type, your melee and ranged weapon attacks deal additional damage of that type equal to your magic damage bonus, and critical hits with those weapons inflict an arcane affliction in addition to the weapon's critical hit effect.
Special
This feat gains the following abilities at higher levels.
Level 1:
Your prepared daily arcane spell may be Rank 1 or Rank 2.
When you cast a Rank 1 spell prepared with this feat, your mage armor lasts until the end of the encounter.
Level 5:
You may prepare an additional arcane spell from your spellbook during an extended rest, for a total of two prepared daily spells. Each spell may be up to Rank 3.
When you cast a Rank 1 attack spell prepared with this feat, you may replace your mage armor's resistance with that spell's damage type as a free action until the end of the encounter.
When you cast a Rank 2 spell prepared with this feat, your mage armor lasts until the end of the encounter.
Level 9:
You may prepare an additional arcane spell from your spellbook during an extended rest, for a total of three prepared daily spells. Each spell may be up to Rank 4.
When you cast a Rank 1 attack spell prepared with this feat, you may add that spell's damage type to your mage armor's granted resistances as an immediate action until the end of the encounter.
When you cast a Rank 2 attack spell prepared with this feat, you may replace your mage armor's resistance with that spell's damage type as a free action until the end of the encounter.
When you cast a Rank 3 spell prepared with this feat, your mage armor lasts until the end of the encounter.
Special
Whenever you cast a spell that deals typed damage, you may choose to gain resistance to that damage type as a free reaction. If you do, you lose any previous resistance granted by this effect.
Leveling Up
At each even level, you choose a new at-will Metamagic. You may choose maneuvers from this class feature or any of your other class features.
At each odd level, you choose a new class feature. Some class features allow you to choose one or more ranked Metamagic; you may choose ranked Metamagics from this class feature or any of your other class features.
You or an ally are hit by an attack from a creature within 5 paces while your mage armor is granting you resistance to a damage type that you can inflict arcane afflictions with.