This is MY art that I feel most pride for... The secret was so unique to discover! I simply used a 'dead' dried pen tip that had NO INK WHATSOEVER; and 'etched' into the paper...making a dragon that was barely seeable except for the 'engraved' lines in the paper... Finally done..? I decided to experiment, and with a stick of charcoal... swiped across the page. It darkly smudged the page EXCEPT the "engraved lines", revealing the picture!