Items can have quality modifiers. These are displayed directly after their name without spaces (e.g. Worn Sword+3) and usually provide bonuses relative to the modifier.
- For equipment they perform a direct addition by the quality modifier to the highest stat of equipment, e.g. a Worn Sword+3 would be ATK+11 instead of the regular version's ATK+8.
- For food they provide an additional 20% to the food's base effect for each point of quality, e.g. a Cherry+2 gives 42 HP on use, 40% more than the 30 HP from a normal Cherry.
- It is unknown whether quality modifiers on rings provide any effect.
- A select few shop decorations can have quality modifiers; these appear to have no effect.
Items with modifiers can only be dropped in dungeons by a defeated enemy (up to +4 maximum), or created by fusion (up to +15 maximum). Items found in chests, or purchased from customers, the Merchant's Guild or Market will always be of base quality.
The quality modifier of fusion results are determined by the sum of quality modifiers of its ingredients. The possibility and ease of a fusion creating a +15 item depends on the number of quality-capable ingredients it needs, the more the better, with some needing so few that +15 is impossible.