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?
After the PCs defeat (or force the rapid retreat of) a villanous necromancer/demon summoner, they discover a book. This book outlines how to summon a demon whose power increases according to the size of the summoning circle used to summon it. And after the PCs examine a map of the country, they find that the layout of the cities and roads match up with the required summoning circle. In fact, the final road that would complete the circle is currently in construction.
With anyone who can find out about the circle and the ritual to summon the demon able to somehow make the final road/line, and destruction of the cities and roads currently in existence out of the question (unless this is an evil campaign- that removes the moral quandary), how are the PCs going to solve this problem?