Dusk & Dawn is a D&D 3.5 game with some heavy house rules and a home-brewed setting. It is High Fantasy and low magic, and it is an Urban game-- instead of adventurers, the PCs will play residents or visitors to a single city. There will be adventures to be had, but they will revolve more around crime, gang wars, political intrigue and underground pit fights than anything else.
The technology level of Volata is roughly where it was in the 1930s, with the caveat that electricity and combustion only really work at night. So your elven paladin is going to have to ditch his celestial motorcycle when dawn breaks, but at least the mobsters he's pursuing will have to switch out their tommy guns.
Welcome to The Warp!
The Warp stretches from what was once called The Sapphire Coast across the rolling, foggy woodlands and into the borders of Parcelish territory. To the North lies the frozen tundra where the dwarven mines surface, and to the South lie the gnomish cities with their rotating lifts and bridges.
And of course, at the center of the Warp, lies Volata. Prettiest little city in the world. Most maddening little city in the world, too. It lies in a perfect position to be a trade city, but outsiders rarely venture there and don't stay much longer. Never overnight, if they can help it-- anyone who sleeps even one wink in Volata is forever subject to the curse.
It didn't always used to be this way. But you know how the story goes: One greedy wizard begins tampering with leylines, and the fragile balance of magic is overturned. Everything goes wonky and suddenly you get The Warp. Of course, the native sons and daughters of Volata like it that way. Things are boring, elsewhere.
Effects of The Warp
Once the curse takes you, you're forever changed. It seems to interact with different people in different ways, but here's the shake: It's tied to the sun and moon.
--Some folks find themselves changed to an animal at dusk each day, only to return to human form at dawn. A lot of them choose to sleep through it. Others don't.
--Some folks turn to stone the second the first rays of dawn touch them, and only figure out how to move around again come nightfall.
--Some get off less easy, and find themselves turned into an alter-ego at night.
Furthermore, all these gnomish and dwarven gadgets you see these days only seem to function at night. Anywhere else in the world they work independent of night or day, it seems like.
Oh, another thing: Be careful going into the woods or setting out of port at night, too. The wildlife tends to get a bit... strange.