Path of Exile 2 Ancient Orb

Effect: A currency item that can be used to reforge a unique item as another of the same item class in the broader sense of the term, such as "flask" instead of life/mana/hybrid/utility flask.

Obtaining

Obtained by combining a full stack of Ancient Shards, which can be obtained from Harbingers from the Harbinger league.

Item acquisition

Spending

Unlike the Orb of Chance, the Ancient Orb is able to reforge sockets and links on the item.Like an Orb of Chance, the result of using an Ancient Orb was not restricted by item level (as of version 3.0.0).[3] Therefore, a unique with a high item level requirement (like Skyforth) may be obtained from any unique item of the appropriate class, regardless of the base's item level. Similarly, when attempting to obtain a unique that drops at low item levels (like Taste of Hate), no advantage is gained by using a low item level base.

Reforging a unique item means the base item type can change when the orb is applied. Ancient Orbs do not change the inventory size of an item, so 2x4-sized "tower shields" for example stay within that group. 

However, from at least version 3.2.0 Ancient Orbs are to some degree restricted by item level or at least influenced by it. This can be useful to boost the chances to get a desired lower level unique (like Headhunter or Lycosidae).