Needs review
Source: Dragon Magazine #344

Description: With a single viper-swift blow you strike and temporarily paralyze your opponent's hand.

Prerequisites: STR 13, Power Attack, Improved Disarm, Combat Expertise, INT 13, Sneak Attack +4d6

By reducing your sneak attack damage by three damage dice, you can make a melee attack that causes your target to lose the use of one of his hands (your choice) for 1 minute. Your target can make a Fortitude save to resist (DC 10 + 1/2 your level + damage dealt). If he fails the save he drops whatever he is holding in that hand, cannot use two-handed weapons, and he may not engage in any action that requires the use of both hands (such as using the Climb or Use Rope skills).

Special

This feat only affects living creatures able to feel pain.