The Church of Law
The Eastern Church differs in a number of minor theological points from the Western Church known to most of the inhabitants of the Dark Country. The most contentious is the shape of their god, which the Easterners believe to be a cube. As evidence of this, they point to a relic they rescued from the wastes of the Desert Lands - an enormous cube they believe to be a section of the God of Law itself. The High Pontiff states that this cube proves nothing as it is clearly nothing more than a large wooden frame with a man yelling loudly inside.*
This cube forms the center of Lawful worship in the City of the Emperor. On the feast day at the beginning of each month, the High Patriarch places his hands on the cube to receive wisdom from the God of Law which he then relays to the Emperor, who is believed to be best able to interpret the Law.
Unlike its Western counterpart, the Church in Zenopolis does not persecute pagans. Instead, it is highly syncretic, reinterpreting pagan worship in ways that make it actually venerate the God of Law, even if the actual pagan cult disputes this "fact."
The Cult of the Fathers
The people of Zenopolis place a great deal of importance on family, ancestry, and history. As a result, the powerful noble families of the city long ago established the Cult of the Fathers in order to venerate powerful magnates who they believe performed great deeds - such as crushing slave rebellions and being really good at farming.
The Fathers are housed in a great system of catacombs that is rumored to intersect with Zenopolis's undercity. There the pickled remains of great men are animated with strange magic known only to the cult. They are poked and prodded with goads and their screams and jerks are interpreted by a learned caste of magicians and idolaters.
The Imperial Cult
Worship of the Emperor is one of only a few cults to be technically proscribed by Zenopolitan and Church law; however, it is "suffered" by the Emperor who has "better things to do" than stop peasants from leaving coins and votive candles at his statues.
The Imperial Cult is considerably more popular among the lower classes than the upper classes - mostly because familiarity breeds contempt. The nobility is all too aware that the emperor is merely the most recent in a line of cunning men who knew the proper application of eyespoons. Still, a small number of young nobles have joined the cult as an act of petty rebellion.
Deposed or exiled emperors are sometimes still worshiped, but none are worshiped after their deaths. It is not uncommon for angry cultists to beset a public statue of a recently deceased emperor in order to slash out the statues eyes with a knife or set of eyespoons.
The Cult of That God We are Supposed to Pray To
No one in the city, not even the cult's High Hierophant and Hierophantess can remember the nature, gender, or purview of the God We are Supposed to Pray To. Despite this fact, the whole of the city believes that if the cult is not properly maintained then Zenopolis will meet great disaster. It is difficult to ascertain where this belief comes from, but surely it must have some foundation in truth or their ancestors would not have created the cult in the first place.
Rites to this god are carefully executed by a double-clergy of men and women for none can remember whether the god prefers priests or priestesses. Each says the ritual words simultaneously and then says them backwards in case that was the way they were supposed to do it. The most prominent symbol of the cult is the Pit and the Fire of the City. It is believed that if either the wood in the pit is lit aflame or if the fire is ever doused the city will be destroyed.
The Followers of the Conquered Sun
A reconstuctivist religion, the Followers of the Conquered Sun believe they have restored worship to a deity that was of vital importance to Man before the Revealing of the Law. Critics note that they have clearly cobbled together a mixture of unrelated mythologies and hero tales into something only vaguely resembling a religion.
Accounts of the Conquered Sun's appearance vary wildly, but believers are quick to observe that the Sun has many "rays" and that their god has known many guises in the past. Indeed, some members of this sect believe that a form of apotheosis is possible in which one merges with the solar godhead.
This sect also produces a large number of ascetics - a fact which Church theologians use to assert that this "young" religion is merely a strange form of copycat. These ascetics typically attempt to bake themselves in the sun, sometimes constructing large pillars in order to more easily have access to the sky in the crowded streets. It is not uncommon to see a an iron box fervently and loudly debating with a stone column in market squares.
The Ones Who Know the Stars
This small but formerly influential cult venerates a set of beings known as the Star Lords. Eastern Church theologians states that these beings are simply angels while Western ones assert that the cult actually falsely deifies the cyclops - a race of beings said to have built many of the miraculously large structures found throughout the World.
Their current leader - a "scholar" named Tsoukalos - was once a manager of a racing team in the Hippogriffdrome. Now he spends much of his time asserting that wonders previously believed to have been built either by the work of Man or by the work of enormous beings was actually accomplished by creatures from beyond the stars. A member of famed explorer Parco Molo's expedition - Erich the Kin of Dan - heard this message and brought it back to Atalia, where he was promptly burned.
The Eastern Heterodox Antichurch
The Eastern Heterodox Antichurch is a brand of devilry that is rumored to exist and perform a number of foul turptiudes - including the slaying of stray animals, the perpetrating of ritual murders, and the playing of strange "adventure" games. Its leader is, according to Western witch hunters, the Low Matriarch - a position which has been occupied by a eunuch in a wig for as long as anyone can remember, but witch hunters believe this is due to a loophole.
It is unlikely that this organization actually exists, as demonic cults rarely organize themselves in the way that Lawful clergy expect them to. Instead, there are a number of micro-cults dedicated to all sorts of demons working their dark arts beneath the city streets. The most popular demon seems to be Moloch, whose leprous, inhuman servants are often seen in the company of hooded men in the bowels of the undercity.
*Those who have actually seen the cube note that it is opaque, clearly metallic, and does not make any noise whatsoever.