Item enhancement using Gems (Amethyst to Emerald)
You can enhance weapons and armor by inserting Gems.

• You need a Gem that matches the item’s level.
• Rough Stones must be processed into Gems before they can be used.
• Enhancement is up to +5.
• The required number of Gems increases by stage: 1 Gem for +1, 2 Gems for +2, and so on.
  • When you insert 1 Gem toward +2, this state is called “+1.5”.
  • Similarly, there are states like +2 / +2.33 / +2.66 / +3 / +3.25 / +3.5 / +3.75 / +4 / +4.2 / +4.4 / +4.6 / +4.8 / +5.
• The success rate for +1 is almost 100%, but it decreases as you upgrade further.
• Be careful when enhancing to +5: on failure it resets to +0.

Enhancement	Required Gems	On failure
+0 → +1	1	Inserted Gem disappears / remains at +0 Success rate: 99.5%
+1 → +2	2	Inserted Gems disappear / remains at +1 Success rate: 80%
+2 → +3	3	Inserted Gems disappear / remains at +2 Success rate: 60%
+3 → +4	4	Inserted Gems disappear / remains at +3 Success rate: 40%
+4 → +5	5	Inserted Gems disappear / resets to +0 Success rate: 20%

Place the Gem on the item you want to enhance while it is equipped.	The above shows the state where the second Gem has been inserted to enhance a +2 item to +3. After this, you insert one more Gem to attempt +3, or it may fail.

Memo
・ Enhancement growth rate for Amethyst–Emerald enhanced weapons/armor (except staves)
+0: 100%　+1: 112%　+2: 126%　+3: 144%　+4: 168%　+5: 200%
・ Enhancement growth rate for Diamond-class enhanced weapons/armor (except staves)
+0: 100%　+1 to +15: +10% × enhancement value
・ Enhancement growth rate for Regent Diamond-class enhanced weapons/armor (except staves)
+0: 100%　+1 to +20: +11% × enhancement value
・ Staff enhancement
Up to Emerald: % = Base + [Base × (12・26・44・68・100) / 57]
Diamond: % = Base + [Base × enhancement value × 10] / 57
Regent Diamond: % = Base + (enhancement value × 26)