Important facts for game play (known to all):
Extremely hot and humid. Average temperature is 100 degrees or more, low temps rarely fall below 80.
Freezing temps are unheard of since the Impact.
Very low Magic environment. (In game terms, spells above 3rd level, from any source, simply fail.)
Arcane magic is shunned and feared by the vast majority of the populace (blamed for the disaster that caused the water level to rise).
Extra-planar magic is virtually unheard of, most attempts to use such fail catastrophically (80% chance) or garner Divine attention (5% chance).
Metal is EXTREMELY scarce, any item crafted largely from metal will have a commensurate cost increase in accordance with the rarity of the material (This is largely due to the majority of the landmass being several thousand feet underwater since the Impact).
Metal has largely fallen out of use as money. The world primarily operates on a barter system using ceramic coins and trade goods. As such, actual metal coins are more valuable than normal.
The current year is 247 P.I. (Post Impact)
Because of the severe shortage of dry land, towns and cities have sprung up that are composed of buildings and pathways constructed on floating platforms. Many of these towns are “tethered” to anchors sunk into the landmass underwater (these are exclusively near the former mountain ranges, now islands as the water is much shallower there). Some towns are “floaters”, meaning they free float around, but generally stay in the same area.
Naval travel is the predominate means of transportation.
Both the gnomish and elven “towns” are domed, underwater cities. The gnomes’ town is heavily polluted and the air quality is very poor due to their reliance on fossil fuels. The elves seem to have discovered an alternate means of energy as they have no problem with pollution at all, but they jealously guard their technology. Any non-elf found with their tech is killed outright, no questions asked, no quarter given. This includes their unique underwater sailing vessels (which are powered by their tech).
Elves were the first to notice that the Magical Weave that surrounds the planet (from which ALL magic originates) was significantly weaker after the Impact. Their celebrated connection to the Weave, which previously contributed to their great longevity, has been all but severed. Elves have a significantly shorter lifespan now. Approximately the same as Dwarves.
Most importantly, WHAT IS THE IMPACT YOU KEEP REFERRING TO??? In short, 247 years ago an asteroid was sighted on a collision course with the planet. The people turned to Divine and Arcane means to try and avert catastrophe, but found only partial success. The Arcane Council, pooling their collective knowledge and talents (wizard and sorcerer) DID manage to deflect the asteroid slightly. No one is quite certain how they accomplished this, as every single individual involved was slain at the time. What is known is that the asteroid ‘bounced’ off the atmosphere of the planet. The Impact was still significant and resulted in world-wide earthquakes, tsunamis and extremely severe weather patterns for months afterward.
Shortly after the natural disasters subsided, it was discovered that the water level was rising. Very quickly. The supposition is that the Impact knocked the planet into a slightly closer orbit around their sun, causing the temperature to rise and the Polar icecaps to melt.
There have been signs of evolution among all the races of the world. Adaptations to the new, wetter environment. Some humans have developed webbed fingers and toes, with a few even manifesting vestigial gill slits (though as yet, no one has come forward with functional gills).
There is currently an ironclad, strictly enforced treaty in place with ALL dragon-kind. Stay away from their lands, or you will be eaten. In return, the dragons have agreed not to raid the islands controlled by the other races, as the majority of food is grown there. Floating and tethered towns are fair game.
Piracy is a HUGE problem. After the dragons, the Pirates are the single most powerful group on the planet. The commonly accepted policy is, is you’re on a ship with weapons and you’re not flying a recognized town flag? You’re probably a pirate and will be fired upon.
Sea monsters have become both larger and more prolific.