Fifteen people who shaped the last two centuries, each one face down under a layer of foil.
Scientists, writers, political leaders and one painter who kept painting himself. Everyone here has been dead long enough that their photographs have passed into the public domain, which is why the credit line under each answer usually says exactly that.
Nearly all of the pictures are studio portraits taken between the 1860s and the 1940s. That was the window when photography had become sharp enough to catch a face properly and formal enough that the sitter held still for it. It also means almost everything in this category is black and white.
Among the names you will meet here: Albert Einstein, Marie Curie, Abraham Lincoln, Vincent van Gogh and Mahatma Gandhi.
Colour is one of the first shortcuts your brain reaches for, and these photographs do not give you any of it. No hair colour, no eye colour, no coloured jacket. What is left is the shape of a hairline, a jaw, a moustache or a pair of round glasses.
The genuinely cruel ones are the bearded Victorians. At twenty percent scratched, Charles Darwin, Karl Marx and Charles Dickens are all just a beard, and the three wrong answers you are offered are chosen with exactly that in mind.
Aim at whatever is unusual rather than whatever is large. Einstein's hair is worth more than Einstein's nose, and a pair of round glasses gives Gandhi away faster than half his face would.
Your score is 100 minus the percentage of the card you scratched. A wrong name scores nothing at all, however little you used. The full rules, the badge bands and an explanation of why the picture stays blurry are on the main page.