The Lost Dwarven City

From the publisher's website:

Deep below Nordaleth Caldera sits the city of Des’gaeth. This old dwarven city was once their greatest city then the plagues came driving them from their homes. For a long time it has been lost, its streets choked with lava, monsters and the fanatics who refused to flee.

Now the city is being rediscovered. Stories of walls covered in joules and ancient relics fill adventures ears, those who have gotten out have other stories to tell. Some say an army is forming in the old city, other speak in hushed whispers about the city itself being alive.