Here is my fleshed-out mantis mascot, Mr. Monocle, for my Monocle Mantis Design alias.You can look at the previous post to see in which part of the poster he will appear in.
You'll notice the shadows are very gray. I have my shadows below my shape layers that are set to multiply. I might try to rearrange things so I can set those shape layers to "color" layer mode and put some colors in the shadows. However, I have decided that my shadows needn't be too realistic as the gray shadows remind me of hand-colored black and white photographs before the age of color photography, which works well with the aesthetic I'm going for.