Ages ago, all of the dwarves who lived in Scaffold, a city deep underground, fled to the surface for reasons lost in time. They sealed off their city with magic so that it would not be plundered.
Over time, another city was built over Scaffold. That was Tenrook.
Now someone or something has unsealed the ancient dwarven ruins and tomb-raiders in Tenrook are exploiting it. Unfortunately, numerous living dungeons are popping up all over, too, and terrible monsters are pouring out into the city.