Culture/Religion: based on fear and respect. Gods are very dangerous creatures, sometimes friendly, often not. Temples are the way to make contact with them... if not easier, then at least more concentrated in one place. Were it not for the temples, gods could be running amok among the people. Therefore, mortals have to keep the gods close to temples, entertained and worshipped. It doesn't make the bad ones any friendlier, though (and is no guarantee some won't go on trips now and then). Still, there have to be priests that are hardy men, able to survive the rigours of their position, get a sufficient number of worshippers to make the gods feel important enough, and mediate the contact between mortals and immortals.
In the Middle Ages, and even up to the early twentieth century, most of Europe's executioners were related: the Sansons and Deiblers in France, the Pierrepoints in England, etc. The reason for this was that, it generally not being socially acceptable to, well, kill people, executioners and their children could, generally, only marry other executioners or their children.
The parallels with massively inbred, Hapsburg-style dynasties are obvious- imagine a rather clever but politically inept satirist noting this, and being sentenced by the latter to a meeting with the former; even worse, imagine a dynasty of deranged and deformed executioners- think Texas Chaisaw Massacre with government funding.
The idea of using tattoos to contain magic powers is not a new one. The Ink gauntlet follows the basic premise of using rare and precious inks to inscribe spells into the skin of a mage or would be spell-imbued person. Some of these inked spells might be permanent, while others might fade after being used once, or a preset number of times.
In the days of old, before the dominance of humanity, the giants were the supreme rulers of the world and their crafts were considered to be the best. These beings venerated the god of the forge above all others and their swords and armors were the best that could be had even in the days of their decline. A hero seeking a masterwork sword might have to voyage long and hard to find a surviving giant smith or cache of rare and valuable giantcraft weapons.
Historicly, we have had plenty of rl groups like the Taliban and the Puritans who supressed anything which was in any way fun. What if there was some group that was the opposite? (which in time would cause problems of it's own for the civilians under their control.)
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.
Nearly every primitive culture has had rituals and celebrations to guarantee the proper passage of the seasons and to ensure the fertility of crops and animals. Oversight of these ceremonies was generally the provenance of local kings or priests.
Suppose that the adventurers dispatch one of these fellows. The local peasants may become hysterical, fearing famine and death will stalk the land. Alternatively, they may want one of the new heroes to become king. For a while, this can be a good thing, but the first time that the crops fail, the superstitious locals will want to sacrifice their new leader.
Rich Romans raised fish in private pools at their villas. A favorite fish was lamprey, a parasitic fish which sucks off blood and flesh but made an excellent meal. A particuarly gruesome punishment for slaves was to be thrown into the lamprey pool, where their flesh was ripped from the bone by swarms of the jawless fish.
In ancient Rome, social appearance and respectability were everything. The most hated men were punished with damnatio memoriae, damnation of memory. Every trace that a person had ever lived was removed. Busts were shattered, freizes were marred, records were struck. Any sign of the hated figure was destroyed.
Pcs learn of high power magics that allow them to banish weapons and suits of armor to some 'elsewhere' place until such time as they need it. reduces encumberances, gets fewer questions, and when the PCs get jumped by thieves in the ally, they can summon their suits of full plate armor with weapons drawn.
Lesser powers would allow them to summon their weapons from another physical place, drawing them to their hands like Luke skywalker summoning his lightsaber on Hoth.
Medieval Britons didn't write contracts. Instead, men making agreements would clap their knives onto an altar and recite the agreement three times to seal a deal. Even after the Normans introduced written contracts, British nobles would wrap the parchment around a knife to authenticate it.
The religion believes in reincarnation, but that you will be reborn in the past. People of today are those re-born of tomorrow, with some discarded as trash. The most pure will be eventually reborn in the mythical paradise-like past, where people lived for hundreds, or maybe even thousands of years.
This goes nicely with beliefs into foresight (you know a little about the future because you have been there), but also to many complaints of how things are going always from bad to worse.
In 1500 B.C. in Egypt a shaved head was considered the ultimate in feminine beauty. Egyptian women removed every hair from their heads with special gold tweezers and polished their scalps to a high sheen with buffing cloths.
An example of a mythological worldview misinterpreting scientific practices occurred in Africa, where an aid organization, focusing on slowing and stabilizing population growth, distributed abacuses with red and white beads corresponding to a woman's menstrual cycle. Women were instructed to move one bead a day, only having intercourse on days represented by a white bead. However, the experiment failed, and the population grew in the households using the abacus. The women believed the abaci were magical, and that they would be protected from pregnancy by moving a white bead into the place of the red bead before intercourse.
The heroes are travelling the great seas by ship. One night when the seas are calm and everything seems fine their vessel is eaten by a great whale. The end? No. They wake in the belly of the animal, it is like a great cave. Full of wrecked ships and strange things to be discovered. Will they make it out alive?
Under the sewers of a large town ancient burial chambers are discovered. If the PCs investigate they fill find that a pale white flowers grows amongst the graves, in the dark.
How do they survive without light? What is their origin? Why in a burial chamber and not just in any old cave?
Can they be sold or do they have any special quality at all? It is up to the PCs to discover.
The members of the party has unknowingly been infected by a mysterious plague and have been spreading the virus for quite some time now while adventuring. They start to hear rumors of all the cities in quarantine after they travelled trough. Will they discover the source of this? Will people start to avoid them, try to kill them?
The greatest tree in the woods has a secret, there is a dungeon under it made from the intricate web of roots. What creatures could reside here? What secrets will the PCs uncover?
A city the heroes visit is in a crisis, the king and queen are getting a divorce. Who shall rule? The inhabitants of the city take sides by tying a red or blue ribbon to their swords, sticks etc. Whose side will the Pcs take?
A plague is spreading trough the lands, the plague is actually an old woman carrying a stick. She walks from farm to farm spreading the plague. Can the PCs stop her without getting infected.
The food that eats you back.
Creatures of nightmare, the thankfully rare Mesnoi have unique form and attributes. Only one Mesnoi at a time will ever be "encountered".
In appearance, a Mesnoi resembles a walnut-sized chunk of freshly-roasted red meat from some uncertain yet familiar, edible animal. The insidious creature camouflages itself quite appropriately whenever it can, by slowly making its way amidst feast tables and trays of roasted meats.
Once eaten by the unsuspecting, the Mesnoi sinks down to the stomach, reforming if chewed, and begins to lap up the gastric fluids, digestive juices, and bile that it craves, like a sponge.
The Mesnoi carrier will experience mild to severe stomach pains during this time.
After a few hours of this (this is the only time that the Mesnoi can be purged with magic, or other mundane means), the Mesnoi transforms into its true form inside its victim, that of a miniature, once more walnut-sized, pot-bellied, devil-horned, snake-tailed imp. This horrid little creature then begins to chew and eat its way out of the victim from the inside out with its tiny, razor-sharp teeth, like a rat forced to do so via torture.
The victim almost always dies a slow, agonizing death. That much is certain. The devilish imp then exits its victim and begins its seventy two hour existence of mischief and malevolence, until it once more turns back into a hunk of roasted meat with the movement capabilities of a snail.