We have more of them now, but I will only write about the first cover of Hexameron.
The poster (aka the cover) with a full-frontal of main character (Gil) indicates that the artist lacks imagination
Jokes aside, the main thing I wanted to show off is that obviously Main Character is holding the Stone which is extremely important in the comic, since it's what ties him to the mystery. Hence the low angle and big hands.
Originally Gil is blue-eyed and blond, so I tweaked the colors so they would fit the overall palette more. I also used more saturated colors than usual.
The light angle here makes no sense, but I wanted to make it look as if the Stone in his hands is the light source since this kind of light angle is typical for telling scary stories in the dark (which is the main idea of the comic).
The smoke was something that just felt right to fit in a "mystical" kind of the cover, it has nothing to do with the plot. Why is the smoke teal? It just went nicely with an orange t-shirt and it felt mysterious too It reminds of the colors of the night forest too, that suits the setting a lot.
All and all it was one of the first real illustrations I did and I suffered with it a lot, so it's hard to tell about artistic decisions and there are no symbolism here.
I will also be changing the cover for every season, showing the MC growing and the stone that changes with him.