Mythical ghost, ancient abandoned castle, floating ethereally in the moonlit corridor, haunting the ancient ruins, dark eerie and misty atmosphere with cobwebs and decayed architecture, moonlight casting eerie shadows, inspired by Edward Gorey, gothic horror, digital illustration, full-body apparition, monochromatic with shades of blue and gray, high-definition detailed texture rendering, 8K resolution, photorealistic, impeccable detailing