Trust your eyes?
A color shows up on screen with six color options underneath. You have about a second to compare them directly. After that the color fades and you're going off memory. How well you see color and how well you remember it, both at the same time.
A color flashes for about a second. Then it goes black. Later rounds give you less time.
Six swatches underneath. They all look close. Pick before the color disappears or try from memory.
Not pass or fail. A percentage that tells you how close your pick was to the real color.
If you pick the exact color you get 100%. The longer your streak, the more each pick is worth. The first rounds are pretty forgiving but the flash gets shorter, the swatches start looking almost identical, and picks that were fine before start ending your run.
The scoring uses Delta E, same formula Pantone uses to compare colors.
Colors get harder to tell apart as you improve.
You keep going until a pick is too far off. No continues, no second chances.
Timer starts at 20s. Good picks add time, bad picks eat it. How much time you get back depends on how accurate you were.