Sapphire Nightmare Blade

1st-level / Diamond Mind

You study your enemy for a brief moment, watching his defensive maneuvers and making a strike timed to take advantage of a lull in his vigilance.   You attempt an Intelligence (Insight) or Wisdom (Insight) check as part of this maneuver, using the target creature’s AC as the DC of the check. You then make a single melee attack against your target. If your check has succeeded you can add you Intelligence or Wisdom modifier to the attack and damage rolls of the attack.