A breathtaking underwater merfolk kingdom nestled in a massive coral reef canyon, towering spires of living coral and ancient stone architecture glowing with bioluminescent accents, massive sea dragons swimming through crystal clear turquoise waters, schools of glowing fish creating rivers of light, warm golden sunlight streaming from above through dancing water caustics, tiny figures of merfolk on horseback riding giant seahorses, epic cinematic scale with reef systems receding into deep blue distance, cool teal and emerald color palette with warm amber light shafts, mysterious ancient underwater mood, dramatic depth and atmospheric perspective, Lord of the Rings cinematic scope, hyper-detailed matte painting, 8K fantasy art