It is the year 3582 on Earth and nothing is as it should be, my 1998 encyclopedia describes a beautiful, peaceful world. How do we get that world back? How do we close these gates and restore the Earth?
The lead New Earth Government of the Cosmic Era
The sky is drab and gray, almost completely covered in rainclouds. What gaps there are open up to show yet more gray. Much like mortal demesnes, the weather is unpredictable, but every so often the clouds unleash their burden of water on the residents of this boring land.
Welcome to the Hell of Half-Nothings. Your stay will be boring, we guarantee it.
The Road… traverses Time—Time past, Time to come, Time that could have been, and Time that might yet be. Some people have the ability to access the Road and travel it from Time to Time and world to world.
As long as any can remember, these certain paths allowed one to travel up to and over 20 extra miles a day by using them. One moment one was deep along a small trail, the next he would find himself 20 or more miles farther down the path without realizing it. All was fine until recently. Reports returned talking of the failure of these areas which revealed miles of ancient paths. The protection hiding them has finally failed. Will it release monsters of ages past or reveal magic of unknown worth?
The local band of 'nasties' (goblins / orcs / whatever) lives in relative peace with the local population.
Along come the PCs and go through their usual heroic monster bashing routine, wiping out the nasties and pinching all their stuff, then continue on their way.
Problem is, they don't kill ALL he nasties. The survivors want revenge and, after spending a few months recovering, start to take it in their own inimitable style (which is not unlike that of the PCs come to think of it).
Next time the PCs are in the area they find themselves VERY unpopular with the townsfolk.