Worlds Enough: Extorris
The world now called Extorris has always been the home of mankind. They had their start here, created or evolved. Near the dawn of human civilization, arcanists opened doors to other worlds, and other species came through. The elves, mostly friendly to man, sometimes reclusive, low in numbers and long of life, masters of magic. The sturdy dwarves, taking up residence in halls in the mountains, places no human would choose to live. The smallfolk, living among the humans, and in the gaps. The doors they came through seemed to be one way, with no return possible.
Not everything that came through would prove amicable. Doors, once opened, could not be closed, and monsters and demons entered Extorris as well, making their homes in the Wastes . . . and spreading the Wastes that they might have more places to call home. Dragons, goblinkind, and wierder things have no intent to share this world with others, not to mention the humans who have been corrupted by the necromantic power that streams through certain doors. Natural creatures are twisted by the fell magics that those and other doors channel, driven mad and hungry.
But man and their allies have advanced, both in magic and in science, and they defend their borders and walled cities with great fervor. With dwarven aid, they developed guns, the steam engine, diesel and biodiesel. They built great war machines to defend their lands from the monsters. Only the elves have objected, noting that the burning of diesel is polluting the lands they try to protect.
Are there gods? No one really knows, though many religions exist. Science and magic, though, those are known to be real.
Welcome to Extorris, the land of exiles. Exiles who, for the most part, do not remember the worlds their people once called home. This is home now, for elf and human and dwarf and goblin alike, and they will all fight to keep it.