The races of the material plane had united. Famine, poverty, plagues and war were but a distant memory, and while there were different nations and countries, there was peace. Technology made the impossible possible and the gods were content, life had even managed to spread past terra. That was over a millennium ago, now all that remains is ruins and wasteland.
The once great buildings are now ruins and labyrinths host to powerful relics and monsters of both flesh and steel. The land is devoid of life, only the rare shred of grass remains, thus druids are a rarity. Due to the hope and belief that they may be able to restore the land many seek to extort their powers, requiring them to live in hiding out of fear of being captured, exploited or maybe even drawn and quartered.
While the tribes of orcs and whatnot might be able to survive in smaller numbers outside the cities, the only remaining civilization is dense sprawling slums that surround and depend on the elites, with cases such as five thousand elites ruling over millions. However, unless you're an elite or have their backing, life will be a struggle. Shootouts are common, gangs are everywhere, organized law is absent, disease is rampant and malnutrition is the standard.
Despite the desolation, traders and nomads do wander the wastes from city to city, selling their wares and relics to the elites and non-elites to make a living. Though it is dangerous, some still hope to become them, toughing it out in the wilds trying not to be killed by stray monsters is still preferable to living in the cities for some.
Since the end of the old world the gods have been discontent. Many have left never to return, while those that remain try to fix civilizations slow decline. However, the elites of cities fear the gods, knowing that they want to strip them of their positions and power, thus outlawing worship of the gods and fighting their followers. Unless in a city under the gods, people of religion, clerics and paladins need to hide their powers.
Technology is also a shadow of its former self. The best current day augments, machines and equipment are the works of novices compared to the relics of past, the mere prospect of salvaging a relic to sell or for personal use is enough to have droves of men and women venture into the meat grinders that are the ruins.
Tldr; think like night city from cyberpunk next to a hive city from Warhammer 40k, inspired heavily by Rebuild world
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