World of Warcraft - item upgrade Upgrading
The upgrade of an Item Upgrades allows players to boost an item upgrader mod's gear rating up to 700 points and give it a bonus. Items can be upgraded if they're in your inventory and you bring them to the kiln.
Certain items can be upgraded for their unique stats (like a perfectly broken point armour that is rolled for Item Upgrader Mod melee PvP) while others like weapons do not vary greatly post upgrade, item upgrader mod and therefore aren't worth upgrading.
Weapons
Upgrades to weapons can improve their numerical stats, such as attack damage, crit chance, and PvE/PvP damage. Weapons come with a flat rate bonus that increases damage per second. Some weapons also have an unaffected bonus that is activated when three or more identical weapons are equipped in a single unit. This bonus could exceed the damage that a weapon upgrade can do on its own.
The cost of upgrading a weapon's capabilities is contingent on the nature of the weapon as well as its current level.
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