Flensing Strike( Eberron Campaign Setting, p. 53)
You have studied a martial style practiced by monks devoted to the Mockery, which has taught you to cut your opponent's skin in a very painful way.
Weapon Focus (PH) (kama) , E xotic Weapon Profi ciency (kama),
Using Flensing Strike is a full-round action. Make an attack roll with your kama. If you hit a living, corporeal foe, that creature must make a Fortitude saving throw (DC 10 + 1/2 your character level + your Wis modifier), in addition to taking damage normally. The DC is increased by 2 if you are wielding two kamas (creatures wielding more than two kamas gain no additional bonuses). The target adds his natural armor bonus, if any, as a bonus on this saving throw. A target that fails the saving throw is wracked with pain, receiving a -4 penalty on attack rolls, saves, and checks for 1 minute. Constructs, oozes, plants, undead, incorporeal creatures, creatures immune to extra damage from critical hits, and creatures with a special immunity to pain are not susceptible to this feat.
An evil monk may select Flensing Strike as a bonus feat at 2nd or 6th level if she meets the prerequisites.