Greetings!
The last few weeks, I've been contemplating a new campaign for my players and my ideas have finally coalesced into something tangible. In fact, the pot is full and nearly boiling over. So, on to the good stuff!
Setting specifics:
Golarion setting, about two thousand years into the future, so expect a more steampunk sort of feel as magic and technology has started to intermingle. Less of the world is unexplored due to ease of travel and technological advances in defense/offense, though it is no less wild. Gnomes are widely credited for this advancement (more details on request).
The Worldwound has been closed.
Good and Evil countries have drifted to Neutrality. All countries are currently shifting towards Lawful, thought most are still True Neutral. There are no more chaotic countries (see TN above) and all (almost all) nomadic tribes, monstrous humanoids, etc have come together in more of a civilized manner. Those that have no longer in existence, either abandoned or hidden from the outside world. Warfare between countries becomes rare.
Direct interference by Outsiders has decreased dramatically. Summoning still works but very few appear willing to remain in the Material plane for long.
Divine magic has experienced a change. The deities that represent Good and those that represent Evil have been slowly fading from the forefront. Less and less worshippers are being granted spells, though the spells are just as powerful and effective as always. These deities still respond to request and communicate with their followers, but are often vague with responses, as if distracted. As a result, the Neutral deities have experienced an increase in popularity, the Lawful ones most of all. Like the Good/Evil deities, the Chaotic Neutral deities are seeming to fade into the background, though they aren't as interested in communicating. Especially Gorum.
So, here is where things get ... really interesting.
No new souls are being born. Pregnancies are resulting in still-births very rarely more than 8 weeks into term. This is not limited to a single race or creature type. Every animate, sentient creature that reproduces and possesses Int, Wis and Cha scores of 1 or higher do not survive long past conception. Even sentient plant creatures are experiencing this. Regular plants seem to be uneffected. Resurrection type spells are still functional.
This has thrown the world into confusion and the church of Pharasma is at the dead center of this maelstrom of confusion. Not even two months into this had many of them whispering about the 'End', the prophecied time when the stream of souls comes to an end and Pharasma's role nears its conclusion. They now have the soul responsbility to prepare the world for this coming event. Trouble is ... that's not what is going on. Pharasma can see the end of the stream and it is not time! Something has gone horribly wrong and she can not see what! She will need to take matters into her own hands.
This is where I want to get some input. I want to flesh out the setting so that it feels realistic to the players, who will be one of the last few souls born. How does the world initially react to something like this? How does their mentality adapt to the thought of oblivion not more than a few 'generations' in the future? How do the longer lived races look upon the shorter lived races and know that even they will perish long after the others?
All this is important. The characters will either have grown up during this time (if short-lived) or witnessed the start of this period (if long-lived). The adventure starts with Pharasma herself appearing in the dreams of the Adventurers, beckoning them to action. This is meant to be a very powerful experience and much will be laid at the player's feet in regards to responsibility. Undoubtedly, the character's will ask why they where chosen. They will ask what's in it for them. They will ask what happens if they refuse. She will answer them truthfully. They are the last vestiges of Chaos left on Golarion and they have no choice if they seek to have a future.
She will not allow them to die and pass into judgement until the mission is fulfilled. Should they fall, they will rise again. Should they fail, they will be left as the only living, sentient creatures on the planet when all the rest have died from old age, with only themselves and the local vegetation for company.
If they ask her if she knows what is going on, she will give them a sly smile and reply that she does. "The forces of Good and Evil have united with Chaos, seeking freedom from their responsibilites in this universe. They have finally realized, as I did long ago, that they can not win in this struggle. They were just clever enough to change the rules. I still have a role to fill and now, so do you..."
I don't know if you have intended this or not, but the basic idea of no new souls is common in Rapture theology, and can be traced to the Talmud and Kabala. There are been a number of fictional treatments of the idea. One especially good one, although not religious at all in nature, is the novel Childhood's End by Arthur C. Clarke, which everyone should read because it is awesome.
Basically, there are many ways to react, and doubtless different individuals, groups and races would choose any of them. In general though, I suspect it wouldn't be a positive reaction.
I do think though that you might have trouble railroading your PCs down your chosen quest line if you really want them to embody the last vestiges of Chaos...personally if Pharasma told me I won't die until I complete the mission I would be highly motivated to not complete the mission. And perhaps learn the simulacra spell...
Thanks for your input, Dave. I took a peek at the Childhood's End wiki page and it does sound fascinating, though not quite what I had in mind. I'll take any good ideas I can though. I mostly came across the idea in the Inner Sea Gods book and it just 'clicked' as a good campaign hook with my own custom version of how the universe was created. Whatever similarities it shares with real world religions is not intended.
Mainly, I want to focus on the overall response to the knowledge that no new children are being born and how people react to their pending mortality. I fully expect exploitation of various magic solutions to prolong people's lives, even resorting to undeath some occasions. Reincarnation, for example, will be popular and even encouraged by a sub-sect of the church of Pharasma (the more heretical branches).
As for railroading the characters, you can see it that way if you wish. The players still have the choice of playing the game or not and their characters have entirely free reign in the game to do whatever they wish. They could ignore Pharasma's mission for decades, or longer, to pursue their own ends. They just can't pass into the afterlife. They can still die, lose levels because of it and be resurrected. They decide to wait until after they die of old age? Forced incarnation, thank you friendly neighborhood Witch! Pharasma has a lot of pull in this setting. She'll resort to bringing them back herself if needed. There is a reason she needs them, which will become apparent later on. They'll have no choice to work with her at first, but eventually, they can help, hinder or completely turn against her.
How ever long it takes, society will begin to break down and I want the character's invested. A long stretch of cold eternity is a good motivator.
Reminds me of "Children of Men" too.