Serpent

Serpent is a once-powerful deity who was imprisoned in the Arch during the human conquest of Diablotin, as a consequence of its weakening power after the upheaval that brought the Seven Gods into power. It was known across nations and on other planes - the shadar-kai called it Vrag, the early people of Aveyrone called it Ophion, in Plascencial it was known as Nashash, "he who solves secrets". It remained imprisoned in the Arch for many centuries, able to affect people who passed through it but otherwise exercising very limited power at most.

Serpent's closest servants, or possibly other aspects of itself, were Emkathon, the Mother of Mercy, and Kavreshar, the Father of Justice. After Serpent's fall, Emkathon and Kavreshar were both forced to take up residence on the material plane. Emkathon, preserving some of the Serpent's blood in a sacred vessel called the Phereia, brought it to the leader of the Wolf tribe, Laeken, and offered him a bargain. She would protect the city and bear him a child, which would bear this blood within it, and in its descendants - the Truebloods (and by now, much of the nobility of House Wolf, one presumes).

Kavreshar, meanwhile, enraged by this turn of events, became an avatar of vengeance, and worked to bring down the Empire and those who were responsible. He was imprisoned in a necklace, but later (inadvertently?) released during the coronation of Marl Kizer, taking on the form of a hellfire wyrm.

Phedre, through her scholarly studies and extraplanar explorations, had became fascinated by the Serpent, and founded the Order of the Serpent Reborn in order to attempt to restore it to power. The Order, with the help of Theron Rademacher, Thea Vermillion, Yanina Trueblood, and Ilphère deQuessenet (all Trueblood descendants), restored the Phereia during a ritual, and later returned it to Emkathon, after she was freed from her long watch over the city.

Reunited, Emkathon and Kavreshar restored the severed Arch, which blended its black and white halves into a mottled grey, and then disappeared into the Arch together, seemingly healed of their grief and anger.

Since that time, priests of Serpent have been able to manifest clerical powers, both on the Shadow Plane and here. Although Phedre was executed for her role in the sacrifices of Butler Belden and Theonée Deverara, others took her place. The church of Serpent is divided, with some still following the darker path of the Order, while others choose the more balanced approach advocated by Sirris, an ancient servant of the Serpent from Am. The shadar-kai followers of Serpent represent yet another tradition.