“ With a huge number of sacrificial victims, another realm long ago secretly bound a Prince of the land spirits, Iorstonn by name, thus ensuring the fertility, and improving the magical defences, of their realm. But binding that Prince to one spot has disrupted the weather and magical patterns (ley lines?) over half the continent. Things have become bad enough that a coalition has been formed to rectify the situation, once divinations have established the cause.
Your party is one of the teams assembled to do the rectification: find the binding object and steal it ('so that we can destroy it here in our realm, of course'...*) or destroy it over there. Presumably the Prince will be grateful to his rescuers and angry at the binders, but with a greater spirit like Iorstonn one can never be sure: such beings are 'tricksy'.
* Of course, the rulers of our realm might want to control Iorstonn for their own ends...”
“ 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?”
“ As far as everyone knows, the Maze has always been there; the strange pair of gates set in the side of a mountain a common feature in every painting of the area, no matter how ancient. One white, one red, nobody knows what they're made of but they resist any attempt to damage them; they're always slightly cool to the touch no matter the weather, they have a very reflective surface, and if you look at them in a bright light, sometimes it looks as if they glow on their own.
The important thing is what's on the other side of them, of course. The Maze itself is a strange place where the normal rules are suspended, and its own set takes their place. It's a place filled with puzzles and riddles, monsters and traps; it's always consistent with itself in any single run but is never the same two times around, and sometimes you could swear it has a sadistic streak, delighting in tricking the unwary adventurer.
It is a dangerous place, as so many people will rush to tell you; most people who go in never come out, and even those who do usually end up scarred for life. They also bring out with them enormous piles of riches, which is why people keep going in anyway.”