From Fallen Sword Wiki
Armor is one of the 5 attribute stats that determine the success or failure of combat.
The other attributes are Attack, Damage, Defense, and HP. Some of the older items in the game also have a sixth attribute, Stamina.
Armor points allow a player to minimize damage dealt by an opponent. The more armor a player has, the more damage that player will block.
A player can decrease an opponent's Armor with the Shatter Armor buff. A player can heighten his/her Armor with the Sanctuary Skill. The Reinforced Armor Enhancement can also increase Armor.