In Last Epoch, the Eternity Cache is a special crafting system that allows players to create powerful Legendary items by combining Unique and Exalted gear. Unlocking and using the Eternity Cache is a key part of endgame progression, offering a way to enhance your equipment beyond standard crafting methods Last Epoch Gold.

How to Unlock the Eternity Cache
To access the Eternity Cache, players must first reach level 50. Upon reaching this milestone, the Temporal Sanctum dungeon becomes available. However, entering this dungeon requires a Temporal Sanctum Key, which can be obtained as a drop from various enemies, particularly in the Monolith of Fate areas where farming keys is more efficient.

Once you have a key, you can enter the Temporal Sanctum dungeon, which is a challenging level 55 area featuring tough enemies and a boss fight. The Eternity Cache is located at the end of this dungeon, next to a stash where you can store items. Note that each key is consumed upon entry, so you will need to farm keys repeatedly if you want to use the Cache multiple times.

How to Use the Eternity Cache
The Eternity Cache lets you fuse two items into a new Legendary item with enhanced stats. The process requires:
1. A Unique item that has Legendary Potential (a special stat that determines how many affixes can transfer).
2. An Exalted item (purple rarity) of the same gear type with four unsealed affixes. Sealed affixes do not transfer.

To craft a Legendary item
1. Place both the Unique and Exalted items into the Eternity Cache while in the Eternal Era (the “past” version of the dungeon).
2. Select the “Seal Cache” option.
3. Use the dungeon’s Temporal Shift ability (default key “D”) to travel to the Ruined Era (the “future” version).
4. Open the Cache again and claim your newly crafted Legendary item.

The resulting Legendary item inherits the base type and original affixes of the Unique item, plus a number of affixes transferred from the Exalted item based on the Unique’s Legendary Potential (ranging from 0 to 4). The item level of the new Legendary is recalculated according to the transferred affixes buy Last Epoch Gold.

Important Notes
1. The Exalted item is consumed in the process.
2. The original affixes on the Unique item remain unchanged.
3. The final Legendary item cannot be further modified or crafted.
4. Items must be of the same type (e.g., boots with boots, helmets with helmets).
5. Class-specific affixes can transfer, potentially making the Legendary item class-specific.
6. Set items cannot be used in the Eternity Cache.