A d10, or ten-sided die, is a die that has an equal chance of rolling the integers from 1 to 10. Its most common form is a pentagonal trapezohedron, in which form it appears in the standard 7-dice set used in role-playing games like Dungeons & Dragons.
Most d10s are pentagonal trapezohedra, which are irregular decahedra (10-sided polyhedra) whose faces are kites. Each die of this form has two sharp corners, where five kites meet, and ten blunter corners, where three kites meet.
The ten faces usually bear numbers from 0 to 9, rather than 1 to 10 (0 being read as "10" in many applications). This is useful when using ten-sided dice as a d100.
Often all odd-numbered faces converge at one sharp corner, and the even ones at the other. The sum of the numbers on opposite faces is usually 9 (if numbered 0–9) or 11 (if numbered 1–10).
This is the only die type in the standard set which is not a Platonic solid.
Although this form is the most common in use today, it did not become popular and widely available until 1980, with the most common form in use before that being the twenty-sided form (below).
The second most common form of the d10 is a regular icosahedron (the same shape used for the d20), which is numbered from 0 to 9 twice over. This form predates Dungeons & Dragons, being used for wargaming in the 1960s, including in naval wargaming situations by the US Naval War College as far back as 1963 (although in this context they were used in pairs as percentile dice).
Twenty-sided dice marked 0-9 were adopted in a limited capacity by hobby wargamers in the late 1960s and early 1970s. An advertisement in a 1971 issue of Wargamer's Newsletter offered a pair of 20-sided dice for £0.42 (GBP) or $1.20 (USD), sold as percentage dice. They appear to be marked with 0-9 twice. These were the dice that Gary Gygax obtained and used as d20s, first in his World War 2-era game Tractics, and later in D&D. He recommended that one of the sets of numbers from 0-9 be coloured in so that it was easier to tell which were supposed to be numbers from 1-10, and which were supposed to be numbers from 11-20.
When d10s were introduced to D&D in 1975's Blackmoor, in which they were used for the levels of ixitxachitl NPCs and for rolling on the random disease chart, it was still expected that they would be the twenty-sided version.
The twenty-sided d10s fell out of use following the development of the standard 10-sided form, particularly with the release of the 1981 Basic Set by Tom Moldvay, which provided 10-sided versions of the d10 and d100 (alongside other dice) and also described how they were to be used in the rulebook.
After the d6, the d10 is the most common die type to be the only dice used in a particular game system, generally used in dice pools. For example, the d10 is the only die type used in the Storyteller System and the Storytelling System, the proprietary in-house systems of White Wolf that are used in games like Exalted and Vampire: The Masquerade.
- ↑ 1.0 1.1 Jon Peterson (2020-02-22). "Identifying the Dice of the 1970s". Playing at the World. Retrieved 2020-03-08.
- ↑ Rob Doane (2019-10-26). "Historical Naval Wargaming Kit Demo (US Naval War College Museum)", 13m 0s. Invicta at YouTube. Retrieved 2020-03-08.
- ↑ Jon Peterson (2014-01-21). "A History of D&D In 12 Treasures", 7m46s. Jon Peterson at YouTube. Retrieved 2020-03-08.