Qi Ripple (3.5e Maneuver)

You strike the opponent in the sides in rapid succession, and suddenly the opponent's body grows weak and shudders...

As part of this maneuver, make a Concentration check against DC 10 + your opponent's Hit Dice, and a melee attack. If your Concentration check succeeds, you gain a +2 bonus on your attack roll, and your opponent, if he is hit, must make a Will save against DC 11 + your Wisdom modifier, or be stunned for 1 round. If your check fails, you instead take a -2 penalty on your attack roll.