Here's a little scrap of 'shrubbery' made out of yellow and blue strokes. The strokes blend both physically and optically to produce a variety of greens.
	I swiftly stroke on some rubbing alcohol with a watercolor brush; here, the alcohol is still wet.
	After the alcohol has dried, I have a different blend of greens, but have lost any blues and yellows (at least in the portion that felt the alcohol). I could now add interesting highlights and shadows if wanted.

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