The Upgrading System is created to make players able to upgrade specific items.
Every upgrade use a specific material, that can be found by using the Craft System.
This process is very simple and easy, and can be made on the character inventory.
To upgrade your Belt it's very simple.
You will need to adquire the Upgrading Crystals.
They can be created using the Craft System.
After that you will just need to "Right Click" on the Crystal, and then "Left Click" on the Belt.
It will be automatically upgraded on your inventory.
Every belt need an specific Crystal to be upgraded:
Cloth Belt + Silver Crystal = Leather Belt
Leather Belt + Gold Crystal = Plate Belt
Plate Belt + Turquoise Crystal = Battle Belt
Battle Belt + Quartz Crystal = War Belt
Note that this process will keep the actual Mix of the item.
Also in case of Perfectized items the stats and Spec will be the same.
In imperfect items it will keep only Mix and Spec, the stats will be all ramdom.
Belt Craft and Upgrade YouTube video guide: