Items come in four different qualities: normal-, improved-, prime- and masterpiece quality. For weapons, higher quality raises the physical damage, and for all armors, higher quality raises the armor class. Absorbing armors also get a bonus to their physical damage absorption. Items with better quality can be found throughout the game, though with a decreasing drop chance, depending on the actual quality. However, golden treasures and bosses have a higher chance to drop items of better quality. There are even some mobs that have a slightly higher chance of dropping those items, e.g. Jintresses and most of the mages.
Here’s a list showing the actual bonuses:
- Enhanced items (improved quality): 10% bonus on physical damage and Armor Class, +1 physical damage absorption for absorbing armors
- Superior items (prime quality): 20% bonus on physical damage and Armor Class, +2 physical damage absorption for absorbing armors
- Masterpieces: 33% bonus on physical damage and Armor Class, +3 physical damage absorption for absorbing armors