Cinematic 8k wallpaper, enormous Cthulhu towering near a coastal lighthouse perched on a moss-covered rock, the turbulent sea crashing below, in razor-sharp focus, invoking megalophobia, stunningly detailed 4k digital painting with subtle organic luminescence, photorealistic and movie-quality rendering, dark and moody atmosphere with luminous reflections, ethereal lighting, subsurface scattering, hyperrealism, breathtakingly detailed and incredibly realistic 64k UHD photo, DSLR-like precision, rendered in unreal engine 5 and octane render, 8k resolution, with a surreal twilight sky adding mystery to the scene.