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World of Warcraft - Item Upgrading The ability to upgrade items allows players to raise the level of their weapons, armor and trinkets. Some upgrades have special effects while others boost the numeric stats. The are essential to the Path of Exile progression. They boost the damage of equipment/ships and combat effectiveness. Typically items that don't vary in terms of requirements after upgrading (like Eth Titans) will see a slightly lower value in trade than the non-upgraded versions. Recycled Item