New work in progress, basically Mars Attacks meets the Wolfman.
Update #1: Main line work is done, bringing in more details to some areas and separating the background lines from the foreground with a slightly lighter shade.
Update #2: Working on the flat colors right now. Occasionally I'll add in darker and light parts to break up the solid colors and to add a bit more texture. Colors are still in flux at this point, but they're nearing their final state.
Update #3: My favorite part, adding shadow. I'll put a multiply layer over the whole image then cut out where I want the light to show through. Usually it's this stage where I'll notice if anything needs to be changed as well, before getting too in depth with the lighting.
Update #4: After touching up a few more spots it's time to add highlights and extra brights spots to finis off the main characters, as well as detailing the background. This will also include altering the line colors in some spots (like the brain) to punch it out more. Once all the small details are taken care of we're pretty much done.