I love that this picture shows the typical creepy castel, and yet still has so many original details.
For example, to me the design of the castle looks like a mix between modern factory and old castle. Honestly, I find an empty factory far more creepy than an old castle, and that's why I like that you played with this motive.
But the most amazing thing about this artwork are the textures. The fence in the front looks so realistic it's like a photo. However, then there's this blue light that gives it a fantasy atmosphere again. I specially like that there are bits broken and the spider webs. Though I think you could have added even more spider webs, probably even more transparent. We've got a fence like that and we always have lots and lots of little spider webs.
What I also like a lot is the fog between the fence and the castle. It gives room for imagination, making you wonder of there's a river with all sorts of creepy creatures in it.
One can see that you put a lot of skill, effort and patience into this artwork, creating this absolutely breathtaking atmosphere.