Know Your Enemy
From Compendium of Worldly Lore
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).