Ruinous Labyrinth

In the age of the Azlaryn Empire, cities were far larger. Luxinae may seem to be a large city in the eyes of the current era, but in its prime, it was merely a single portion of the grander city. Buildings would stretch for miles, to the point there was very little space between any two cities that could be said to divide the territories of the arcane lords.
  Now, millenia later, the buildings are all but eroded away…but they are not all returned to dust. Beneath the lands of Noctuin, the remnants of the cities reach out in vast labyrinths of dark tunnels, some collapsed but others intact for the length and breadth of the nation.
  To find an entrance is truly the dream of many scholars of the ancient world, but wandering too far into the darkness could mean never finding your way back out.
  It is not known what all lurks in the dark labyrinth, but it is more then just demons prowling the halls.