As opposed to my usual combination of airbrushes and blender tools, the former is what will make this fanart series shine. At time of writing, the Mixer Brushes were a brand new addition to Fresco, and I spent around an hour of testing before rendering. The most useful tool and setting I found for my style was the Detailer Mixer with the color set to 0% opacity (be sure "Reload Color" is turned on), turning into a fairly smooth blend tool that expertly mixes colors.
After the initial shading and rendering, I brushed in a very soft white airbrush to emphasize the light from background. I followed up with the "burn tool trick," adding faint black to a blank layer set to the Overlay blending option. To bring the setting together, I added the villainous lime green that every character feared as a rim light and soft ambient. All of these layers were possible by copying a layer mask made from the original flat color.