We have story in Persian mythology about a evil king called (zahhak or dazidahak) that rolled ancient Persia. He was kissed by a devil on his shoulders and from the places that devil kissed two snake has grown up. The snakes were feed on youth brains. Every day he have to sacrifice two young people to feed the hideous snakes. this story has been a main effect on this illustration.
At the final stage I just came with two composition thumbnails. As I said before I have to put the rider in center focus that’s why I draw him alone close to the viewer eyes and then I have to explain what he is riding and what he is doing so I draw the second rider in background. Having path for the viewer eyes is very important.
In this composition the first thing that the audience will see the rider and then with the whip line that goes to the second rider and then to the far background.
After I figured the best composition I started roughly with big brushes blocking the main shape really fast and after I blocked the main shapes with correct value I eventually decrease the brush size and slowly start giving details to the piece.
Notice at the beginning you start fast with big brushes and then slowly you decrease your brush size and slow down your painting speed and of course I used some textured costume brushes for this.