Those scratch-off art books. What are your tips for covering in areas you scratched (like with your nails)?

My wife has tried permanent marker, but the shade of black is too glossy for the dull luster of the black scratch off material. She recently scratched one with a couple nails real good, not realizing the piece was sitting where it was.

So, suggestions for a flat, matte marker perhaps?
ty

Submitted January 26, 2019 at 11:29PM by AndrewWaldron http://bit.ly/2UgnUI4