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The Item Upgrader in World of Warcraft The War Within introduced Valorstones, and Harbinger Crests as two currencies to upgrade equipment. They can be traded at the item upgraders NPCs Cuzolth and Vaskarn. Each item can be upgraded to its maximum level for a particular slot at a time. After that, upgrades to that slot will be less expensive. Additionally the pity system introduced with The War Within lowers extreme variation in the chance to upgrade. Upgrades Upgrades are parts that enhance performance or add new functionality.