Apparently there is no "official" statistics concerning what skills are needed to use certain qualities of items. This is my best guess based on looking at the crafted items available to me:
Melee Weapons : Strength +10
Range Weapons : Balance +10
Heavy Armor : Constitution +10 AND (highest) Skill +25
Light Armor : (highest) Skill +25
Medium Armor : (highest) Skill +25 AND Constitution *1.5
Jewelry : (highest) Skill +25
Big Shield : Constitution +10
Small Shield : Constitution *1.5
Example 1:
I have a piece of Medium Armor of quality 105 (I love my medium armor)
This means that my highest level need to be at least 80 AND my Constitution needs to be at least 70.
Example 2:
Inversely
If my highest level is 126, my strength is 100, my constitution is 125, and my balance is 120. Then the best I can buy is:
q110 melee weapon
q130 ranged weapon
q136 Heavy Armor
q151 Light Armor
q151 Medium Armor
q151 jewelry
q135 Big Shield
q187 Small Shield
And I have just realized that I forgot my amplifier stats.... CRAP
Well, this is my best guess, I shall make a follow-up in a moment
Melee Weapons : Strength +10
Range Weapons : Balance +10
Heavy Armor : Constitution +10 AND (highest) Skill +25
Light Armor : (highest) Skill +25
Medium Armor : (highest) Skill +25 AND Constitution *1.5
Jewelry : (highest) Skill +25
Big Shield : Constitution +10
Small Shield : Constitution *1.5
Example 1:
I have a piece of Medium Armor of quality 105 (I love my medium armor)
This means that my highest level need to be at least 80 AND my Constitution needs to be at least 70.
Example 2:
Inversely
If my highest level is 126, my strength is 100, my constitution is 125, and my balance is 120. Then the best I can buy is:
q110 melee weapon
q130 ranged weapon
q136 Heavy Armor
q151 Light Armor
q151 Medium Armor
q151 jewelry
q135 Big Shield
q187 Small Shield
And I have just realized that I forgot my amplifier stats.... CRAP
Well, this is my best guess, I shall make a follow-up in a moment
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I am a Fyros. What more do I have to say other than that?