Twist the Knife (3.5e Feat)
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 Twist the Knife [General]
You know how to make your blows especially painful — something that can be extremely useful if you’re attempting to distract a spellcaster.
Prerequisite: BAB +4
Benefit: You can perform this maneuver any time you make a melee attack. You take a –2 circumstance penalty on your attack roll, but if you’re successful the target must make a successful Fortitude save (DC 15) or take a –2 circumstance penalty on attack rolls and skill checks for the following two rounds. In addition, if the victim was casting a spell when he was struck, the DC of the Concentration check required to maintain the spell is increased by 2; this is in addition to the 2 point skill check penalty if the caster fails his Fortitude save.
Special: A fighter may take Twist the Knife as a bonus feat.