# A Twenty-sided Die

Dice are used in games around the world to generate a random number. Traditionally the die is cubical; however there are multiple forms of non-cubicle die, such as, the 20-sided die. Ancient die were typically made from bones, wood, or rock. Today, die of all shapes are usually made from resin.

The 20-sided die can be traced back to the Romans, however this ancient tool for generating numbers was put to a new purpose in 1974 in Lake Geneva, Wisconsin. In 1974 Gary Gygax incorporated the 20-sided die into a new game he had invented. That game was called Dungeons & Dragons.

Before adopting the die, Gygax’s now-famous game asked players to randomly draw numbered poker chips from a bag. This method was cumbersome, limited the game’s portability, and was not sufficiently random. Gygax adopted the new die because the shape of the 20-sided die offers an equal five percent probability for each outcome. The more commonly used six-sided cubical dice do not offer equal probability and are relatively predictable in their results. With two six-sided die, for instance, rolling a 6, 7, or an 8 is frequent, while 2’s and 12’s are rare. This does not create equal probability in a combat with monsters!

In his fantasy-based tabletop game, Gygax introduced Americans to a new kind of role-playing game where all players needed was the rule book, seven types of dice, pencil, paper, a sheet of graph paper, and their imagination. Players create their own personas, endowed with characteristics achieved by a roll of a die. Once the brave companions have started their adventure, the 20- sided die became the most important die used in the game. That die controls the strategies and attacks made by players; an ancient tool put to new uses!

Notes:
Duke, Galen. Dungeons & Dragons: 40 Years of a Wisconsin Invention, Wisconsin Public Radio, 20 Jan. 2014, https://www.wpr.org/dungeons-dragons-40-years-wisconsin-invention. Accessed 21 Dec. 2017.

Dungeons & Dragons; New to the Game, What is D & D?, Wizards of the Coast LLC, dnd.wizards.com/dungeons-and-dragons/what-is-dd. Accessed 21 Dec. 2017.

Kusher, David. Dungeon Master: The Life and Legacy of Gary Gygax, Wired, 10 Mar. 2008, https://www.wired.com/2008/03/dungeon-master-life-legacy-gary-gygax/. Accessed 21 Dec. 2017.

Metropolitan Museum of Art, metropolitan Museum of Art,https://www.metmuseum.org/art/collection/search/551072. Accessed 21 Dec. 2017.

Morrisy, Anne. Dungeons & Dragons: A Journey of Imaginations, At the Lake, Geneva Lakes Area Magazine, 25 Nov. 2014, atthelakemagazine.com/dungeons-dragons/. Accessed 21 Dec. 2017.