Lighting looks little funky on ths one. You lit the entire tower very white But the ray is coming from behind top. 2 solutions here. First one is you just leave the light as it is, just lit the right side plane of the castle, as well as all the buildings. The other way is leave the light on the castle, but change the light direction. Also , in general, need more texture and layers and layers of detail on mountains. Look at edgar payne or aspevig I recommended to you guys. You just have to try to paint like their landscape digitally on your piece. just open the sample right next to your painting and try to copy and apply.