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Firstly, enhancements are permanent bonuses to specific powers. They are obtained by killing enemies, or buying from a Quartermaster, and are more rare and expensive than Inspirations. They get more expensive the higher level your character is. When an enhancement is applied to a power, it is locked into that power, and cannot be removed. It can, however, be overwritten, by just applying a different one. When overwritten, the enhancement previously locked into the power is lost, and cannot be recovered. Enhancements can alter all different stats and are permanent, but can only affect one power, and until the higher levels, do not affect them as much as Inspirations.
The invention system is used by players to make advanced enhancements, inspirations, and salvage that can be used for personal gain, or sold for profit. All invention items require a recipe and an assortment of salvage (listed on the recipe itself) to complete the creation.