The world guaranteed this Reaction Test Game! No. 1 Education Category in 4 Countries. Also it took the top 5 and top 10, in 28 and 38 different countries. Let's play the best Reaction Test Game! About Fastest: "Fastest = Fast +Test". You just need to act quickly to get high grade to following stimulations. 1. Screen turns Yellow! 2. Device Vibrates! 3. Spider Falls!