First of all, I would like to make note that I haven't read any of Terry Brooks' works, so if there is some more extensive meaning to some elements in the piece then they will sadly not be anything I will notice or be able to comment on.
That said, here's what I can offer:
I like the way in which you've divided up the piece and chosen to separate certain elements so drastically, as it well showcases those elements. That said, some further separation not only of the elements but also in the way they're coloured would really help to make certain parts of the piece pop. For instance, colouring all of the sections individually (the red, the white and the black) would give each section its own presence. This would also help in dividing up the foreground (black), middle ground (white) and background (red). As an example of this, there's some red-tinted colouring that shows up on the background and the foreground but not on the smoke in the middle ground. This combines the foreground and background but creates a disparity in the presence of the middle ground smoke.
Looking at just the foreground, the figures in the foreground are very pronounced, with evenly defined edges and that sort of definition would be expected across all of the foreground. However, the ground that they appear to be walking on is blurred and ill-defined.
With regards to the smoke, I can't actually tell where the smoke is meant to be coming from. With how low to the ground the smoke is on the left side of the image, one would expect the fire to be coming from behind the characters, but plumes of smoke tend to start thinner at the point of origin and bloom outwards. If the thinner section of smoke on the right of the image was the point of origin then there's no reason for the smoke to originate so high above the characters. Additionally, smoke tends to become less concentrated and lighter as it moves away from the point of origin and dissipates, but here the smoke is darkened all along the bottom of the plume, which further confuses the point of origin and the direction the smoke is meant to be blowing.
I would recommend checking out some minimalist pieces for some examples of stark foreground and background separation as well as some interesting ways of applying textures and additional cosmetic colouring to pieces of this nature.
That's all the critique I can offer up at the moment.
Hope it was helpful~
Thank you so much for your critique and advice! I was trying to capture a mental image I had while reading, and didn't put much thought or research into the behavior of smoke. In fact, I never actually decided if the white part was smoke or clouds. Anyway, your critique is very much appreciated, and I will take it forward with me as I grow as an artist.