A Legendary item is a composite item made up of a unique and exalted item. Unique items must have at least 1 Legendary Potential (up to 4), and the exalted item must have exactly 4 unsealed affixes. The exalted item can have a sealed affix, it just cannot be added to the Legendary item.

When combined in the Eternity Cache, you are granted a Legendary item. The Eternity Cache is located within the Temporal Sanctum dungeon. Running higher tiers of the dungeon will allow you to create Legendaries out of higher level uniques.

The Legendary item is the same as the unique item with affixes added to it from the exalted item. The number of affixes selected is equal to the legendary potential of the unique item used. When using the Eternity Cache at the end of Tier 2 or higher Temporal Sanctum, you can choose one affix to guarantee being moved from the exalted item. If the Unique item had more than 1 Legendary Potential, the rest of the affixes are chosen at random.

The quantity of legendary potential that a unique item drops with is influenced mainly by the level of the zone which it drops in, but corruption also increases it slightly. Increased rarity mods, character level or any other modifiers have no effect.

The amount of Legendary Potential that a unique item will generally drop with is relative to the item’s base power. High powered or very well scaling unique items are difficult to find with even one legendary potential, and low powered or leveling items are much more likely to have even more than one legendary potential. This is done so that most unique items have more similar overall power potential.

Corrupted items cannot be used to create Legendary Items.