This is a project I decided to do after seeing this artwork by Cyril Labranche:
With the artist's permission I used his work as reference for this model.
There are files for normal solid model, hollowed out version with the windows open if you want to put LEDs inside and then first time for me: dual extrusion model with the fortress and the mountain separated. Please note that I have not tested this myself in practice. My print is the hollowed out version that had a small mistake resulting in missing geometry, I have since fixed this for the release.