Both Onyx and Midnight moved to the edges to wait for the sun to shift. They thought it would be easier to explore when the added light mana from the sun would not be making the area even harder to move around in. They found that as the sun shifted, the light reflected by the glassy dunes would shift as well.
When clouds would pass overhead which was rare in a desert, it would cause a quick shift in the light mana making spikes of light mana or spears of light mana fly through the air or melt certain areas of sand again.
This was how the entire area had gotten this way, the movement of the sun and the light mana stayed together causing more sand to be melted in to glass. There was also the fact that the sand and light were being forcefully merged in this area which would surely create a unique environment where a few unique plants or monsters might grow.
