Combat Skill (CS) is a measure of combat ability, weapon strength, and all-around battle prowess. The higher a character's Combat Skill, the more dangerous they are in a fight. Combat Skill can be raised and lowered a variety of ways, including:
- Psychic attacks, e.g. Mindblast.
- Certain Backpack Items, such as Alether Potions.
- Possessing some Special Items while encountering a specific creature.
- Unique weapons, such as the Sommerswerd. Some weapons may add Combat Skill only against specific foes.
- The Weaponskill Discipline, with the appropriate Weapon.
- Certain pieces of Armor, such as the Silver Helmet.
Combat are determined by die rolls and a simple comparison of the player's CS value and the opponent's CS value via subtraction (player's CS - opponent's CS).
Note that the player is at a considerable advantage in fights when facing opponents with similar Combat Skill. Lone Wolf only starts losing more endurance points than his opponent at -5 combat ratio or worse, while the combat ratio must be -7 or worse for Grand Master to be at the same disadvantage. However, it is generally hard to recover EP during a story, making attrition a serious obstacle.