I went on an internet search yesterday to finally find a proper term for the technique I am occasionally obsessed with, involving drawing with hard pencil on soft paper, coloring over that with wax crayons, coating all that with ink or paint, then scraping the ink back off, which leaves it in the indented original pencil lines.  “Indenting” is a technique used in pencil drawings, I learned. The rest is something between Wax Resist and Scratchboard. Every time I go through a phase of playing with this technique I gain a little more control, and it still has never stopped feeling satisfyingly magical to me.