The wind picked up further still, especially when the ground started to shiver, and the multicolored sand started to give way to something yards away. In the marbled desert floor, something started to rise. The sand pouring off of it obscured what it was at first, but as it started to tower over them, it became quite clear that Mephisto was very serious about sandcastles.
This one, however, wasn't quite sand. The stone underneath the desert was dark and strong, thicker and sturdier than any handmade brick or mortared stone, and the sheer black-green stone facade of the building looked practically impenetrable. The sand melted in a hot yellow ooze against the windows, dripping down into tinted glass panes, and the parapets were jagged and spiked. Once the wind died down, it had done its job and cleared acres of the land around them of the sand. Mephistopheles stood and glared in the general direction of north, and there sprang an oasis, and from there grew a lush, green yard around the castle. He didn't do well with creation, really, just molding the world to his needs. It took a LOT of energy.
He put his hands behind his back once he was finished and turned to her again. "Shall we?"