An intricate and futuristic submarine train travels through an enchanting underwater world, resembling an old steam engine with its detailed metallic surfaces and glowing lights shining through small windows. With a steampunk-inspired design and cyberpunk aesthetic, the train exudes a sense of mystery and adventure as it navigates through bioluminescent waters, surrounded by floating islands and cave-like structures emitting vibrant orange light. The overall style of the concept art draws inspiration from renowned animation studios, blending elements of fantasy and sci-fi to create a captivating and immersive visual experience.