Hey kiddo. I haven't done this in a while, but I think I understand the concept.
We can assume the setting is as the beach, but if you want to be more precise, we are positive this part of the story is taking place at sea. "Omnari sped toward the island, increasing the speed of her Hover-Ski so it rose a full foot above the water" This quote proves that the setting is taking place on water, and, "....severed metal head in a shattered crown staring sadly out to sea," this quote proves it is at sea. The mood being created in the story is located in this excerpt of the story. "...full foot above the water. There was just enough sun to power it...." It is trying to evoke a sunny, ordinary yet untraditional feeling in the reader.