In some regions, various occupations might be exclusively staffed by members of a particular race or ethnic group. As examples, a city's butchers might tradtionally have orcish blood, or all the dwarves in an area could be expected to join the miners' guild (even if they personally have nothing to do with mining). Those who violate these stereotypes may find themselves in conflict with local customs or idiosyncratic laws.
On some of the islands off the coast, the rites of the local fertility god revolve around ceremonial death and rebirth. The religion's priests have overcome this cycle, however: Each of them is actually undead, ceremonially slain and "reborn"! Their religion is otherwise unremarkable, being an odd offshoot of the mainland's religions. The priests vow to resist their undead cravings, seeing these as the "cycle of life" attempting to reclaim their spirits.
According to the Journals of Lord Goidol, the people of the Southern Cities wear heavy coats all the year round, despite the stifling tropical heat. They claim that to do otherwise angers the gods, and it is true that visitors who refuse to don the local garb are often struck down with a paralytic fever.
There is a land where every person wears spectacles. Those without eyeglasses are considered to be the lowest stratum of society, so adventurers without glasses are treated like outcastes. It certainly would explain those heroes wearing sunglasses for no apparent reason...
In a city where the justice system features judicial dueling, plaintiffs and defendants are permitted to request a champion to take their place in the duel: Someone chosen by lot from among the foreigners in the city. When anyone first arrives, they are given an enchanted ceramic pendant that marks them as a candidate for "court duty".
Wealthy folk entering the city are often escorted by burly guards, paid to carry pendants on their behalf: They elude court duty in that way.
Adventurers may seek work as a rich man's proxy or may find themselves magically summoned to serve as a champion.
In an isolated mountainous region, the local miners build their stone huts right next to the sarcophagi of their dead. In the winding tunnels of their mines, the spirits of their ancestors toil alongside them, sensing where the best deposits will be found and guiding their picks' strokes.
"The world has an immovable dark red sun in the centre of the sky that produces very little light. The heat is totally unbearable and the aroma of delicious cooking meat is in the air. To look around it appears as though you are surrounded by giant black mountains with no vegetation anywhere. The ground is soft and an oily liquid flows into your footprints. Travelling reveals nothing else."
Any character without some resistance to fire or heat is slowly being cooked. The ground if you haven't guessed it is the cooked meat.
I've wanted this world to be part of a dimensional hopping "chase". I thought maybe to populate this world with giant carnivorous beetles or perhaps this could be a "Nirvana" for deceased or living (but dimension travelling) fire dragons.
Perhaps I've just been grilling a little too much meat or perhaps there are some great ideas out there on how to spruce up the place. Any suggestions?