This world is premised on an ascension mechanic similar to clicker games. At first you begin with almost nothing; you leverage that into a little more power, and a little more, and then a lot more, and then eventually you convert all your worldly possessions into some sort of meta-level bonus and start over from the beginning.
The 'player' of this particular metaphorical clicker game is the local instance of the Serg template, and his ascension cycle involves deconstructing the universe, claiming the souls of all the people who have lived in it this round to add to his power base, and building a new one from scratch.
Soul-claiming is a less ominous process than it sounds. The souls are perfectly intact, exactly as they were at the moment of death. He can't examine or modify their contents, although he can identify specific individuals and choose to reembody them without waiting for them to incarnate automatically. His power increases with the number of unique souls in the pool, and to a lesser extent with the number of incarnations each soul has experienced, but the souls are not damaged or drained or consumed in any way; he just gets more powerful as the counter goes up.
The natural process of human reproduction in this world will sometimes draw a soul out of the pool and incarnate it, and sometimes create a brand new soul for the child. Usually, if two souls who had children together in a past iteration have children together again, their children will strongly tend to come out as reincarnations of the previous set, but this isn't an ironclad rule; souls can show up with completely different parents from their previous incarnations, and established couples can have their established children out of order or produce new ones unexpectedly. Souls may move freely between sexes, and how their gender varies by circumstances is a matter of individual personality.
When a soul dies, it does not return to the pool, but instead becomes temporarily inaccessible while it waits to be collected at the end of the world; souls in this state can't reincarnate naturally or be incarnated deliberately. There's a time window of a few minutes between death and disappearance, but if someone dies and Serg isn't right there to collect them at the time, he has to wait for the next cycle of the world before he can incarnate them again. It's theoretically possible that he might someday figure out within-cycle reincarnation, but he hasn't yet.
Deliberately incarnating a soul will by default result in a young adult human who is capable of moving and speaking and recognizing objects in their environment but knows very few facts. Leaving a few hundred of these scattered across a field is generally an effective way to found a society, but it'll go a lot better if you stick around to teach them some things.
It's also possible to incarnate a soul more subtly, by waiting until a new human is about to be born and inserting your chosen soul before they develop their own or draw one from the pool. In this case, they will not have any special effects from having been incarnated on purpose rather than naturally.
The process of destroying and reconstructing the universe is difficult and somewhat risky, but, relatedly, worthwhile in the long run. Most of the risk comes from the fact that there are creatures outside of the universe which would like to come in, and it would be a bad idea to let them. The more the local Serg increases his power level through successive worldcycles, the easier it is for him to fight them off.
The universes he builds are finite: there is some land, and some sky on top of the land, and some sort of lighting arrangement, and the whole thing is enclosed in a solid outer shell whose exterior is swarming with nameless eldritch horrors.
Because of who he is as a person, Serg tends to set himself up as ruler of each new world as he creates it, and for the same reason he tends to set up their societies in ways that play to his kinks. A fairly high proportion of world-iterations have explicitly sexist societies where women are legally anywhere from second-class citizens to outright property, because Serg thinks it's hot and finds it convenient. The ones that aren't like that are mostly also the ones where he doesn't rule the world, or takes a very hands-off approach.
Broadly, you could divide the styles of world-iterations into a few main categories each with a set of common subtypes:
- "Sexist fucktopia" (most common): Serg rules the world and has set up its legal and societal structures/institutions to be convenient for him and his horrible kinks. Subtypes include:
- generic: he pushes things in directions he finds attractive without making a significant effort to play up one particular aspect of the scenario. Women's rights are usually minimal but extant.
- torture-heavy: he specifically pushes for violence, especially sexual violence and especially by men against women, to be more common and accepted/expected. For this purpose, women are legally enslaved, since letting them have any rights would make it less convenient to hurt them on a whim.
- slave-centric: women are legally enslaved, but the focus is on ownership rather than mistreatment. He likes these ones for scratching his possessiveness itch.
- common-property: he pushes for a scenario where women are not only legally enslaved, but are considered a common resource if no one lays a specific claim to them.
- generic: he pushes things in directions he finds attractive without making a significant effort to play up one particular aspect of the scenario. Women's rights are usually minimal but extant.
- "Lazyverse": an iteration where he didn't want to bother ruling the world, so he decided to do something else instead. Subtypes include:
- mysterious disappearances edition: he doesn't seek out any kind of public reputation, and instead conceals his presence from the public, hiding himself away in an inaccessible lair and emerging only to surreptitiously abduct people in ways that leave his impact lost in the noise of ordinary folk going missing for ordinary reasons.
- threatening landscape feature edition: he doesn't seek power, but he does seek recognition. He sets himself up somewhere very obvious and concentrates his attention in the area nearest his decadent citadel.
- nap edition: he goes to sleep for centuries at a time, waking only when the stability of the universe is threatened by hostile incursions.
- mysterious disappearances edition: he doesn't seek out any kind of public reputation, and instead conceals his presence from the public, hiding himself away in an inaccessible lair and emerging only to surreptitiously abduct people in ways that leave his impact lost in the noise of ordinary folk going missing for ordinary reasons.
- Miscellaneous:
- hands-off rulership: he sets himself up as ruler of the world, but then doesn't try to shape its society into any specific mold and mostly lets people get on with their lives however they like
- non-sexist fucktopia: he molds society into a convenient shape, but leaves the sexism out of it. He doesn't do these often enough to have a full set of established subtypes, but usually he includes legal slavery as a way to obtain victims without the population at large having to worry that any of them might be next. He'd do them more often if he hadn't gotten into the habit of the sexist fucktopia framework early on; after all the time he's spent shaping societies into sexist fucktopias in particular, making a non-sexist one hardly ever occurs to him and seems much more difficult when it does.
- snowglobe world: he makes the world small and well-fortified, and instead of incarnating a reasonably sized starting population and letting them reproduce naturally, he incarnates specific people on an individual basis. Some of them he keeps immortal and childless for a long time; some of them he kills almost right away. These worlds gain him hardly anything in terms of power growth, but he indulges in one occasionally because he finds them relaxing.
- hands-off rulership: he sets himself up as ruler of the world, but then doesn't try to shape its society into any specific mold and mostly lets people get on with their lives however they like
I haven't fully worked out what the deal is with magic in this world. I know that Serg's basic capabilities include matter creation/manipulation/destruction, retrieving and incarnating souls, sensing things going on inside his world, and fighting off eldritch extradimensional invaders. There's probably also a magic system available to the world at large, and he might be able to manipulate the nature and availability of environmental magic features with his cosmic powers, but I don't think he can overhaul the functionality of human-usable magic. Though he might be able to tweak it? Not sure. Also I just... have no idea what it's like or what's going on with it really at all.
Serg being the person that he is, while lots of his world-iterations are very horrible, none of them involve cultural institutions of overt child abuse. Even in the worst of the sexist fucktopias, it's still illegal to torture children regardless of their gender. The age of majority for this purpose is generally 16-17.
He has experimented over the years with various possible calendar systems, but eventually standardized on a 360-day year with twelve 30-day months. All his worlds have their celestial lights scheduled precisely to this framework. He also usually forms worlds as a roundish blobby continent surrounded by ocean, with his place of residence on a nice tall mountain in the middle, but he experiments more freely with geography than cosmology because quirky geography can be fun but badly standardized calendars are just annoying.
I also haven't fully decided what the world was like before he began cyclically destroying and recreating it, and how exactly he ended up in that position to begin with. His pre-ascension self might have been a prince, or he could have been just some guy; both options have their merits. Overall, I think I lean "just some guy", because a world-ruling Serg who didn't grow up expecting to rule any worlds is a new and interesting angle.
Worlds where he actively meddles in society tend to end up speaking a version of the same language he's been speaking all his life; worlds where he lets people develop their own society also end up developing their own languages.
