Working with the nice dark mixes I discovered when I did the dark swatches, I will paint in this little black cow - not using black, but using a few mixes of colors to make him look dark against the pale stone wall. I also have Lunar Red Rock - a color I found in the bottom of my bag of pigments - which should be a nice addition to the little cow since it granulates.
This is just the first step and the wall needs some work to bring it some depth and interest and not look so flat. Since the wall is stone and light, I'm allowing myself to use opaque colors there - Chinese White mixed with some American Journey Apricot (a mix of 3 pigments) that makes a warm pinkish beige color. Maybe some cracks in the wall here and there will add interest.
The bg greens need to be pushed back, too, but I may wait until I get some color on the cow (actually a little calf) before seeing how it all comes together.
This is something I'll have the students do next time we meet. Or they could paint a very pale cow against a dark wall. As long as they work on getting some good darks in their paintings, whatever they paint.