Unarmed is a universal Combat Style common to all characters, measuring the ability to defend oneself without the aid of weapons. The Unarmed skill covers the brawling and wrestling techniques known by that culture. However there are, of course, specific styles that enhance the ability to fight without weapons, offering advantages to those who learn them as a separate Combat Style
As Unarmed is a Combat Skill its Critical and Fumble effects are covered by the rules for combat, as detailed in the Combat chapter.