High-poly photorealistic ancient leviathan: 80-ft serpentine body with obsidian-black overlapping scales and indigo bioluminescent veins along flanks. Head with multiple barnacle-encrusted jaws, glowing cobalt-blue eyes under armored brows. Scaled frills tipped in phosphorescent cyan run down spine. Underbelly plates coral-encrusted, tinged with iridescent green algae. Pectoral fins wide, bat-like, ragged translucent membranes. Tail splits into three serrated prongs. Include wet-skin specularity, subsurface scattering for fins, displacement maps for scale ridges, drifting plankton particles. Neutral serpentine curve pose with fins extended, clean quad topology, game-ready, 8K PBR textures.