Prologue
The first of the dungeons appeared about a hundred years ago. Strange, large pieces of architecture that no one returned from after entering. At first the people left the strange structures alone. But the dungeons had an adverse effect on the plants and animals around them making them larger, more aggressive, and more deadly. Even the Darkness of night itself became an unbeatable beast.
And so the adventurer's guilds were formed in order to protect people from monsters and find a way through the dungeons. Finally, a dungeon was cleared and disappeared, leaving behind the surviving adventurer's and various riches.
The adventurer's guilds boomed in popularity after that and soon more dungeons were cleared, leaving behind peaceful safe zones. Unfortunately new dungeons appeared almost as quickly as old one's were cleared.
To this day the first of the dungeons has still not been cleared and there are those who hold out hope that if it can be cleared the world will finally be free of the dungeons...