Armor Class

Armor Class. An object's Armor Class is a measure of how difficult it is to deal damage to the object when striking it (because the object has no chance of dodging out of the way). The Object Armor Class table provides suggested AC values for various substances.
Object Armor Class
| | Substance | AC
| Cloth, paper, rope | 11
| Crystal, glass, ice | 13
| Wood, bone | 15
| Stone | 17
| Iron, steel | 19
| Mithral | 21
| Adamantine | 23