^^ I think that might be the jewel crafting part of the guide
“ Craft is : Zod jewel crafting : +(1 to 2)% to Spell Damage
Weapon/Shield/Armor/Helm/Gloves/Boots/Belt:
- Spell Focus:15
- Faster Cast rate : 10%
- Faster Hit Recovey : 15%
- Faster Block Rate : 15%
- Fire Spell Damage : 4%
- Life : 50
- Requirement -10%”
Since you’d be trying to get the -10% requirement jewels for the heftier items.