Maze of Marble

Miners have a legend of a marble expanse deep in the Unders. They say it spreads for miles, with the finest purest white marble. Streams of color cutting through the gleaming stone. To bring a cartful of this marble back to Sanctuary would make any man wealthy. But the place is a labyrinth. Miners say it is a temptation, and promise that leads to ruin. No one escapes it, the paths seeming to shift and bend back upon themselves.   But then if no escapes, how did the legend come to be?

Localized Phenomena

The marble here lies on fault lines that intersect and shift. The paths and passages are known to open and close in what seems like an unpredictable manner. Some have passed through it without being smashed into a fine paste, so there must be a way. Without a guide who knows the shifting of the marble it is a deadly quest to enter this maze.
Type
Natural Wonder
Location under