This is a rough value study for the painting "Forest Conflict"  My paintings are all in acrylic or acrylic and oil.  I paint on either canvas panel or gesso primed Masonite.  Every painting starts as a 4x5 inch sketch that I work up in grays as a value study.  I wash the surface in an acrylic tone then add darks and lights in umber tones.  I finish with color glazes in either oils or acrylics.  I think this is similar to the approach Frazetta used.  He was an early and continuing influence on my work and a true 20th century master.