Needs review
Source: Kalamar's Player Guide

Description: You can learn your opponents fighting style and take advantage of weaknesses.

Prerequisites: Patience, WIS 13

After 3 rounds of combat, you gain a +2 circumstance bonus to attacks against a single opponent for the duration of the battle.

Special

If you have Knowledge (fighting styles) skill and successfully determine your opponent's style of fighting, you gain an additional +1 bonus to attacks (making the total for this feat +3).