DELTA DICE: This set includes two red dice, two blue dice and two green dice. When you add up the spots on a normal die, they equal 21. Each of these colored dice spots equals 21 as well. However, specific numbers have been chosen for each die. Start the game by introducing just one of each of the colored dice. Ask someone to choose a die and roll it ten times. You choose a different colored die and do the same. Statistically, when the points are tallied, you will win most of the time. The reason this works is because there is a delta pattern to winning. Imagine playing Rock-Paper-Scissors with someone. If you knew what they were about to choose, then you'd know what to play to beat them. The same is true here. Green beats red. Red beats blue. Blue beats green. However, there is a twist! For the next round of games, you bring out the second die of each color. The numbers on these dice match exactly with their corresponding color. After explaining the delta pattern of winning, you proclaim that, with a pair of colored dice, their chances of winning will be doubled. In reality, it does just the opposite. Now Blue beats red. Red beats green and Green beats blue. The delta pattern reverses. It's amazing! Made in the USA. This is a great gift for the math minded or for those who like gambling-related games.