Every armour, from a simple cloth shirt to a king's crown, can have at least one part that's not as good as the others. With this skill, an experienced armoursmith can swap out a worse part with a better one, improving the armour's overall quality. Skill and components needed vary by target's starting quality:
Exceptional+ needs 51% skill, one strip of primal material and 5 enchanted parts. Good+ needs 26% skill, 5kg divine material and 5 exceptional-quality parts. Standard- needs 5kg exceptional material and 5 good-quality parts. The 'parts' are grips for held-slot items, and armour parts for everything else.

Each armour can be upgraded up to three times -- worse armours can be upgraded more than better ones. Each upgrade 'tier' goes up to a maximum 5 out of 5, and must be completed before the next one can start. The effect the merchant can give is based on this skill chance, repair armour skill chance, int score, and their mastery of the material of the armour. Syntax: use upgrade armour at <armour> The armour, the components, and all required tools must be in the merchant's inventory.