A dark fantasy gothic castle constructed from black obsidian crystal with faceted surfaces and sharp geometric angles, tall spires reaching skyward, glowing purple and magenta stained glass windows illuminating the structure, perched dramatically atop a mountain peak surrounded by layers of misty blue mountains fading into the distance, a large luminous full moon dominating the night sky with wispy clouds, warm orange lights at the castle base, painted in a digital art style with photorealistic rendering, influenced by science fiction and fantasy architecture, mysterious and otherworldly atmosphere.