Upgrade Cores

Upgrade Cores are a type of Core used for increasing stats on armor and weapons. The +X after the name of an item indicates how many times it was successfully upgraded. Eg, "Titanium Blade +4" has been upgraded 4 times.

Usage
If you've never used an Upgrade Core before, you are best to practice with an Upgrade Core(Low). Be aware that the stat requirements of the item will increase when you upgrade it.
 * 1) Unequip the item you are upgrading
 * 2) Left click on the item upgrade button in your inventory, and insert item and Upgrade Core (Low)
 * 3) Left click on item upgrade
 * 4) If successful, the item will now be +1 (or more depending on the original grade of the item), in a very few situations, the item is upgraded with +2

Core grades
There are 4 grades of Upgrade Cores. Each grade is used to upgrade different grade of gear and weapons:

Chance of failure
There is a chance of failure after the item is +3.