This is beautifully done Rem. It's simple, yet breathtaking.
I love how you've created a focus point on the horse, it works incredibly well for this angle and size of manipulation. There's something that you've done with the horse that really draws the eyes (other than the blur), bravo on that ^^
The sky looks amazing, and depending on your take on it, those could be stars or ash falling from the sky. (I for some reason really like the thought of it being ash, but that's just me ).
There are only a few things I notice that could use a tiny bit of touching up. The first is how much blur is on the background. I really like the idea, but there's so much it's almost distracting. I might tone it down just a tiny bit.
The second thing is towards the top of the sky there are a few clouds whose edges are a bit too hard (this is just an opinion thing) I might soften them up a little ^^
I really like the series of works you've been doing lately and I hope to see more!