|Upgrade Core (Low)
||Increase the quality of Citrine, Shadowsteel, Aramid or lower grade equipments. (Right click to use)
||Item, Basic crafting
A comprehensive list of cores can be found here.
Upgrade cores are mainly used for upgrading items level(+1, +2, etc), more info can be fond here.
Other types of upgrade cores are as follows:
Craft: Basic Craft level 6
Field: Bloody Ice, Desert Scream, Green Despair
Dungeons: Weakened Lake in Dusk, Weakened Ruina Station, Chaos Arena Lv1