A submerged metropolis lies in the depths of an oceanic planet, its skeletal towers of corroded steel and glass rising from a seabed carpeted in swaying fields of bioluminescent kelp in shades of green and crimson. Bubbles rise lazily from fissures in the cracked streets, catching the faint turquoise light filtering from the surface far above. Patrolling the ruins is AQ-72 "Depthstalker," a droid engineered for aquatic salvage. Its streamlined frame is a fusion of sleek, hydrodynamic curves and matte-black ceramite, streaked with barnacle-like growths of calcified algae. Its head is a tapered wedge, crowned with a dorsal fin of articulated sensors that ripple like a living thing, while its optic array consists of four bulbous, glowing orbs arranged in a diamond pattern, pulsing with a deep amber hue. Its arms are webbed with retractable membranes, ending in trident-like claws etched with glowing runes, and its lower body tapers into a coiled, serpentine tail studded with propulsion vents. Swimming in its wake are its companions—sleek, eel-shaped droids with translucent bodies revealing churning currents of silver nanites, their surfaces rippling with faint electric arcs as they dart through the kelp. 0r0105, Chiaroscuro Lighting Style, partially covered in shadows