Champion

As a swift action, you can declare a single combat challenge to one foe within 50 feet and in line of sight. Upon doing so, you gain a +1 bonus on attack rolls and a +1 dodge bonus to AC against that foe as long as no one else threatens that opponent or until the single combat challenge ends. If another combatant attacks you or your foe, the challenge ends and you take a —2 penalty on attack rolls and to AC for 1 round. Though you can declare a single combat challenge at will, once you

Defeat an appropriate number of challenging foes in single combat. These combats must not be interrupted by other creatures, and the foes must not have already been substantially injured or impaired prior to combat with you.

Your bonuses for single combat increase to +2. In addition, any confirmed critical hits you make against such a foe deal an additional 1d6 points of damage.