1. Catalys :
Daikatana / Great Sword = Critical DMG +10%
Helm = Hp +50
Sword / Katana = Attack +2
Orb / Crystal = Magic +2
Critical DMG can be inserted JUST in helm and weapons
HP +50 can be inserted JUST in boots and suit
Attack +2 / Magic +2 = Weapons , Gloves
Gloves = usually random
Critical rate = Lvl 2 upgrade (so you have to be very lucky)
This picture explains lots better :
2. Upgrading
The max upgrade it's +7
from +4 to +7 , if your upgrade fails , your upgrade will go down with 1 . example :
Gloves +4 , use UCH , fail => Gloves +3
Gloves +3 , use UCH , fail => Gloves +3 (can't go down from +3)
Gloves +6 , use UCH , fail => Gloves +0 ! (+6 fail brings the item to +0)
You will find it very difficult to make your item even +5 .
To have higher success rate you need to use a Core Enchant which gives you more success rate when you upgrade .
Perfect cores are used to + instantly (meaning that you can't fail with those) .
So for your item to be +7 I recommend you use Perfect core

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