Variable Defense
Swordmage Utility 6
You summon the strength of the elements to shield you from damage.
Personal
Effect: Choose a damage type: acid, cold, fire, lightning, or thunder. You have resistance to that damage type equal to your Constitution modifier. As a minor action, you can change the type of resistance to any other listed damage type. This resistance lasts until the end of the encounter.
Variable Defense is a daily power available to swordmages at the 6th level.[Dr367:56]