Wait—it says " blue," but it's printed in red. What's going on? This multi-player brainteaser game is designed to befuddle, and strenghten your brain. Everyone plays at once as you race to match up cards that don't match—it sounds easy, but it's surprisingly challenging. None of a Kind is based on The Stroop Test, one of the most-cited papers in experimental psychology. It studies the relationship between the brain's processing speed and executive functions, focusing on regions of the brain involved in planning, decision-making, and managing real-world interference, such as multi-tasking. In other words, playing None of a Kind improves your brain's processing speed.