Canny Strike [General]

Prerequisites: Int 13, Clever Fighting, Weapon Finesse, base attack bonus +6.

Benefit: When using either a light weapon or any weapon that can be used with Weapon Finesse, such as a rapier or whip, you deal an extra 1d4 points of damage with each attack per point of your Intelligence bonus. For example, a fighter with an Intelligence of 15 and wielding a cedeku deals an extra 2d4 points of damage with each successful hit. As with other bonus damage dice, this damage is not multiplied when a critical hit is confirmed. You cannot use this ability when wearing medium or heavy armor or when carrying a medium or heavy load. Targets immune to sneak attacks or critical hits are immune to damage from Canny Strike.

Source: Star and Shadow, p. 51