So here's my entry for Jazza's challenge of the month. It was probably a bit too ambitious for the time I had, but I still manage to do something that's not too bad.

Also, the different ''colors'' were achieved by using different saturation of the same hue. And that was a challenging way to work for me.

You can also see a few closeups at my here at my blog: http://cedricgoillustration.blogspot.ca/2015/07/challenge-of-month-fear-final-version.html

Edit: I reuploaded a bigger version so we can see a bit more of the details :)