Pantheopolis, the City of Many Gods!
Pantheopolis, whose armies ranged far and wide! Their legions captured countless cities, and with each victory, the city's gods were carefully transferred to their new seat of power.
Pantheopolis! City of temples, built with the rivers of tribute flowing to the capital. City of priests and imported rituals. City of blessings uncounted.
Pantheopolis! And when there were no more enemies to conquer, city of Ecumenodiplomats, who crept into towns and flattered their gods into departing. City of Theoarchivists, who searched scrolls and tablets for forgotten gods. For if the city achieved greatness under the guidance of a hundred gods, think of what could it achieve with a thousand.
Pantheopolis! City of blessings. City of curses. And, in time, a city where they could not be distinguished. Pray for fertility and receive barrenness from a rival god slighted by your inattention, or birth litters of dozens as gods compete to outdo each other. City where every wish becomes a prayer, and every prayer an invitation. Orphanages overflow with least demigods; armies are paralyzed by conflicting omens, crops grow out of season. The gods jostle and bicker, ignoring rites and forgetting their duties.
Pantheopolis! Former capital of an empire, now a collapsing nest of divine feuds. In desperation, the Five Oligarchs have issued a decree. Let the gods depart!
And so, this is your task. Carry a god to a new place (with their implied consent). Find, build, or reclaim a temple. Instruct the locals in the correct rites.
The Divine Exodus
The PCs are the usual mix of unsavory types, contracted to transport a god (and their physical presence as a statue or similar object) to a new land. Some money up front, but more money on their return (plus whatever they can fleece from the locals). It's reverse loot-for-XP; the more stuff you haul out of the city, the more XP you get.
All the useful gods (of safe travels, of warfare, of localized bandit smiting, etc.) have already been shipped out, surrounded by small armies and appropriate pomp. Don't expect a lot of help from the statue/stone/petrified frog/shield you're hauling.
In their lust for divine power, Pantheopolis may have unearthed or appropriated gods that were best left forgotten and buried. Traditional tentacular horrors, flame-and-skull cults, etc. Finding a settlement willing to take such a god off your hands may be difficult. Some image rehabilitation might be in order.
The League of Inveterate Atheists
The gods, great and small, have caused nothing but trouble for humanity. They should stick to their own affairs and leave humans alone. The League of Inveterate Atheists undermines shrines, tosses statues into bogs, bludgeons clerics, and generally attempts to reduce the total amount of faith in the world. The Divine Exodus is a great opportunity to pick off a few small and feeble cults.
Members of the League are typically wracked with philosophy, and can be distracted by complex logic problems. They wear disguises, use false names, and avoid direct and clear-cut blaspheming.
Of course, there are the usual OSR enemies. Cults of rival deities. Generic monsters. Other adventuring parties looking to take credit for someone else's work.
An enormous crowd went and filled the camp. After the Dictator had taken the auspices and issued orders for the soldiers to arm for battle, he uttered this prayer: "Pythian Apollo, guided and inspired by thy will I go forth to destroy the city of Veii, and a tenth part of its spoils I devote to thee. Thee too, Queen Juno, who now dwellest in Veii, I beseech, that thou wouldst follow us, after our victory, to the City which is ours and which will soon be shine, where a temple worthy of thy majesty will receive thee."
When all that belonged to man had been carried away from Veii, they began to remove from the temples the votive gifts that had been made to the gods, and then the gods themselves; but this they did as worshippers rather than as plunderers. The deportation of Queen Juno to Rome was entrusted to a body of men selected from the whole army, who after performing their ablutions and arraying themselves in white vestments, reverently entered the temple and in a spirit of holy dread placed their hands on the statue, for it was as a rule only the priest of one particular house who, by Etruscan usage, touched it. Then one of them, either under a sudden inspiration, or in a spirit of youthful mirth, said, "Art thou willing, Juno, to go to Rome?" The rest exclaimed that the goddess nodded assent. An addition to the story was made to the effect that she was heard to say, "I am willing." At all events we have it that she was moved from her place by appliances of little power, and proved light and easy of transport, as though she were following of her own accord. She was brought without mishap to the Aventine, her everlasting seat, whither the prayers of the Roman Dictator had called her, and where this same Camillus afterwards dedicated the temple which he had vowed.
After being thus victorious in battle and capturing two camps and nine towns belonging to the enemy and receiving the surrender of Praeneste, Titus Quinctius returned to Rome. In his triumphal procession he carried up to the Capitol the image of Jupiter Imperator, which had been brought from Praeneste. It was set up in a recess between the shrines of Jupiter and Minerva, and a tablet was affixed to the pedestal recording the Dictator's successes. The inscription ran something like this: "Jupiter and all the gods have granted this boon to Titus Quinctius the Dictator, that he should capture nine towns."
That the art of statuary was familiar to Italian Italy also and of long standing there is indicated by the statue of Hercules in the Cattle Market said to have been dedicated by Evander, which is called 'Hercules Triumphant,' and on the occasion of triumphal processions is arrayed in triumphal vestments; and also by the two-faced Janus, dedicated by King Numa, which is worshipped as indicating war and peace, the fingers of the statue being so arranged as to indicate the 355 days of the year, and to betoken that Janus is the god of the duration of time. Also there is no doubt that the so-called Tuscanic images scattered all over the world were regularly made in Etruria. I should have supposed these to have been statues of deities only, were it not that Metrodorus of Scepsis, who received his surname from his hatred of the very name of Rome, reproached us with having taken by storm the city of Volsinii for the sake of the 2000 statues which it contained.