The Arbiter Attunement is one of the Restricted Attunements that is only granted to one who has successfully completed a diplomatic task for one of the visages. Typically it involves assisting in a political matter between visages and human cultures. Arbiters have demonstrated that they can be trusted with delicate matters, and thus, they are employed by visages for additional assignments.
Spire Elementals are bound to assist an Arbiter in any way possible, since their tasks are often of great importance to the visages.
The Arbiter attunement specializes in transferring mana into others. Its primary mana generation type is transference. Its secondary type is life.
The Arbiter attunement purifies mana that is sent through that specific attunement, allowing for safe transfer into other humans. This is the core function. It can be used to both restore lost mana and to temporarily increase the power of an ally over the normal maximum limits.
Warren Constantine, a famous Arbiter in Caelford, was integral in the process of constructing the first generation of artificial attunements. He is listed as a principal contributor in the earliest papers published on new attunement development, until he abruptly disappeared from the public scene in 402 AF.
While Caelford does have a handful of other Arbiters, it is believed that the Arbiter attunement is not actually a necessary part of the process. Instead, modern approaches to crafting artificial attunements rely primarily on Biomancers, a local attunement that allows for manipulation of a subject’s mana. While the details of the process have not been publicly published, it is believed that creating an artificial attunement requires work on the parts of both Biomancers and Enchanters.
It is possible that earlier-generation artificial attunements were performed by Arbiters rather than — or in addition to — Biomancers. This may have been abandoned due to dangers in that process, or due to the comparative scarcity of Arbiters. Unfortunately, the exact details of the process are currently considered military secrets, and thus not yet available for public consummation or discussion.