Wardbreaker

You have studied techniques designed to pierce magical protections.
  Benefit: Once per day, you can attempt a melee Touch Attack against an opponent that you believe has a Deflection Bonus to AC. If your attack is successful, your foe's Deflection Bonus to AC is halved (to a minimum of +0) for a number of rounds equal to your Charisma modifier. You can use this ability twice per day at 10th level and three times per day at 20th level.