I did this card using the image by Mark's Finest Papers which is below:
You can see what it looked like both before and after filling it in solidly.
Presto! An instant, custom silhouette stamp!
I stamped the seahorse with Tuxedo Black onto some glossy I had brayered over
and then I used my black Copic marker to fill it in.
I will admit to an oops though. I smudged a spot and hated to toss my work so I disguised it with a hand-drawn fish net.
Amazing what you can do when you want to isn't it.