Underwater Kingdom.

A magnificent underwater kingdom sprawling across the ocean floor, with grand palaces built from living coral in rose, gold, and turquoise. Bioluminescent jellyfish drift overhead like floating lanterns, casting shifting blue and violet light across pearl-inlaid streets. Mermaid sentinels in ornate shell armor patrol near towering gates with giant clamshell arches. Schools of tropical fish weave between spiraling seashell towers. Columns of sunlight pierce the deep water, illuminating a central throne carved from a single enormous amethyst.