As for tools to work out a picture there are many that Odd employs. I gett the impression that hes of the mind to use damn near anything under the sun if it can help him reveal a masterpiece. to begin with there are a number of. Brushes but none that look the way they look in the art store, his favorites look like sturdy bristle brushes as old as time. Cleaning brushes with soap is ridiculous and terrible practice so he stores them all laying in a puddle of oil in a paint tray, sometimes for a very long time. Otherwise they sit pleasantly in turpentine. Theres a practice among landscape painters of destroying brushes, even with scissors to achieve more random brushstrokes. This is extreme but i think Odd does appreciate a well seasoned brush. As for palette knives there are many as well as any scraping tool thatll release the beauty. Sandpaper is used to abrade the top layer of dried paint and scrub out elements he will repaint, but also perhaps to redraw with, or to describe forms, or the create depth, or atmosphere, or you name it. That said his paints are not harmful and basically edible. He does not use lead or cadmium or mercury or any of the severely toxic pigments. There are of course rags and fingertips that play a role in painting as well and like i said do what it takes to make it great.