AP is an abbreviation of Attack Points, or Action Points. When you have filled your adrenaline bar, you can make an Adrenaline Rush (special ability). Weapons & Leader with attack bonus to AP: Small bonus +3, Medium bonus +5, Large bonus +8. Every attack you make and hit an enemy you gain +20 AP + (weapon bonus if any) + (leader bonus to AP if any) Every hit you take give you minimum +1 to +20 * AP + (weapon bonus if any) + (leader bonus to AP if any). More damage taken = More AP