Four Great Mages
The Four Great Mages were powerful mages selected according to traditional competitions and rituals whose charge was protecting the Kingdom of Maisraln from malign forces, and they were the protagonists of Maisraln. After November 2017, the protagonists of the Suijing Cycle were the early mages selected to establish the Four. In Maisraln, the Four Great Mages were Lyra Felise, Elvar Murchaidh, the Ashen Darkside and Gawyn Harowcal, and their progenitors in Suijing were Kanja Reiki, Kensaki Zihau, Erin Xingmay and Ainas Tacar, in each case plus any fleeting keys. The presence of fleeting keys sometimes meant that the number was changed, so some sources referred to the Five Great Mages or Six Great Mages.
Each of the Four Great Mages took up a specific mantle as the Helundtu, Hermadiúir, Bynmidelle or Ramolace Heru (other notable titles introduced via fleeting keys included the Derasen and the Royal Cartographer). The Helundtu was responsible for potions and healing; the Hermadiúir for protecting and extending magic itself, and defending against powerful mages; the Bynmidelle for social cohesion and protecting the natural order; and the Ramolace Heru for magical creatures, particularly dragons.
On the timeline, it is notable that the Four Great Mages lasted beyond the Kingdom of Maisraln itself, which fell in 1487, lingering on as an enduring source of protection and order as the kingdom descended into misty anarchy. The institution was established in 571 by King Jonathan II's Great Magical Charter, drawing on earlier knowledge and tradition, and it lasted until 1620, when the key characters in Maisraln declared that they would have no successors and established the Council of Mages to supersede the Four Great Mages.