Use silver and golden keys to open chests to obtain weapons and armors. The golden chests may contain the best weapons and armors. Use extra equipment to upgrade other items.
Upgrades
Upgrading allows you expend unneeded equipment to increase the total level of an upgraded item. You can also Refine an item, sending it back to level 1 but allowing it to level up faster than a regular item. Find a balance between refining and upgrading an item to make it strong very fast.