This illustration was commissioned by Wizards of the Coast for their Dungeons and Dragons - Monster Manual Book 4, which is out this month.
In the brief description Wizards requested something along the lines of their Yuan-Ti monster, which is a king of warrior snake thing.
I am usually given a description to illustrate but for this project they let the artists design the monsters and then wrote the text around them. We were just given a vague brief like evil plant or lizard creature. It was really cool to work like this. I created 9 monsters for this book. You can see more in my DA gallery or on my web site [link]