Background you need to know to understand what I'm talking about.
I'm a gamer, a role-player, I run role-playing games. Exclusively, I run and play
GURPS which is a game "system" that enables me to use the same rules for a multitude of genres. I've been using GURPS for about 17 years and one of the main genres I've run is fantasy.
To do so, I created my own fantasy world and as time went on, more detail was added thereby helping to make the world more dynamic and many adventures were had in this world.
One such adventure pitted a band of fairly powerful mercenaries against a near omnipotent necromancer bent on ruling the world. Unfortunately, this band of adventurers failed to comprehend the magnitude of their opposition and were sumarily thwacked for it.
Nearly a year later, the religious order that funded them assembled a new, more powerful band of characters chosen from the finest heroes from all over the continent. They set out, with a small army at their disposal, and sought a weakness in the defenses of the psychotic that now ruled an entire kingdom and showed no signs of stopping there.
As you will soon see, the details get a little hazy from here on out. Storytellers speak of a great battle that cracked the sky and tore the earth as if it were rotten flesh. Some say the Dark Overlord defeated these new saviours, but skeptics ask where he is now. Others say the heroes defeated him and scattered his remains to the elements. In either case, neither the heroes nor the Overlord were seen again.
Of course, no one really had time to consider where they had gone and how. This had been the epic battle betweeen good and evil. A conflict of that magnitude takes it's toll on its surroundings. The world suffered greatly. The people were free from the threat of an undead ruler, but now their very existence stood on the brink. The sun was cut from the sky and the world saw an unending twilight. The evil minions, plucked from the nether dimensions to be used as pawns, now were freed without their master to control them. Many other hells set upon the earth. Entire kingdoms cast into eternal flame, volcanoes and earthquakes gutted the landscape. Plagues and famine drove entire civilizations to starvation. And mana, the very essense of magic, of life itself many believe, mana was drained from the world. Used up in the final war they say. Great archmages, once able to summon a feast for a city could no longer call upon their magical powers for even the most menial of tasks. All that gave the world life was gone.
This eternal twilight became the new home to everyone. Entire races were wiped out by starvation, exposure, and predators. Those that found a way to survive would be forever scarred by the atrocities necessary to sustain them.
Suddenly, as if everyone at once awoke from the same terrible nightmare, the sky parted and the sun rose.
Most thought the great fire in the sky was a new horror set upon them by their acursed world. With the sun brought back the seasons. A new spring came, plants once again answered to those with the knowledge. Clusters of people turned into villages, trade routes were established, and a semblance of a society began again. But as the peoples spirits rose, the minions of the dark sought once again to supress all that is good and natural.
A new order of heroes must be summoned. New magics are to be found and harnessed, and this evil must be vanquished, lest we return to the eternal twilight.