Archon

In The Free Cities an Archon is someone entrusted with safeguarding an Arcstone, these were usually picked from among the wisest and most accomplished wielders. The position of Archon came attached to immense responsibility as the stones were the lifeblood of the city and it's people. Likewise, Archons were extremely powerful and influential both; within their city, holding significant sway over local government; and outside of it, through The Council of Archons.

Archon Krux

Possibly the most infamous Archon of all, Krux, The Harbinger of Ruin, who betrayed all principles of his position and, through the use of Krux's Hand, destroyed five of the Arcstones before ultimately destroying his own and himself, in the events of The Shattering.