Wall of Blades

Your weapon mastery transforms your blade into an extension of your arm, allowing you to wield it with
the speed and timing needed to make a precise block.
When an enemy makes a melee or ranged attack
against you, you can make an attack roll. Use the
higher of your AC or your attack roll as your
effective AC. You can't use this maneuver if you
are denied your Dexterity bonus to AC. You can
decide to use this ability after you learn the result
of your opponent's attack.