h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Missed one... the 30-sided dice also exists and is used in a few gaming systems. The dice appeared around the same time as the one-hundred sided die.

And it should not be forgotten that the 100-sided die (or D100 in serious gamer's parlance) can be simulated with two distinct 10-siders, one to be the 'tens' and the other the 'units', and in fact that most 10-siders are labelled 0-9, with a double-0 being read as 100.

The same is also done with three dice to create the rare D1000, never to my knowledge manufactured as a single (presumably football-sized) polyhedron.

Attempts to use two 6-siders to create the D66 are of course mathematically flawed, unless counting in base-6, but allow a greater range spread while still using a type and number of dice likely to be found in your average game of ludo.

The Prophet

Combining two similar die, or even dissimilar ones, provides for impractical dice rolls without having to figure in modifiers. While you can get a result between 1 - 16 with 3 six-sided dice and deducting two from the result, you could also roll two 4-sided dice and construct a table of reference with 11, 12, 13, 14, 21, 22, 23, 24, etc.

It would have been nice to see a twinge of historical data on this table. While chance has been determined by the use of some form of dice for thousands of years, the introduction of other multi-sided dice is more recent. It would have been interesting to find out who introduced them and why. I may look for the answer myself.

Cribbing from the Encyclopaedia Brittanica:

Sophocles says that dice were invented by the Greek soldier Palamedes during the seige of Troy. Herodotus claimed the Lydians in the days of King Atys as the first dice players. They were both full of it.

The earliest dice were probably knuckle-bones, marked on four sides and used in casting auguries, and they have been found in the archaeological exploration of many ancient cultures.

Cubical dice have been found in Chinese excavations dated to c.600BC, and in Egyptian tombs dated c.2000BC. The Sanskrit epic, the Mahabharata, contains references to gambling with dice (one of the central characters losing his throne, his kingdom, his brothers and their wife, as I recall).

There are also instances of ancient pyramidal, pentahedral and octahedral dice.

So there you go.

Also, the D100 scores over additive dice combinations in that it maintains an even probability spread. On a pair of fair D10s, the probability of obtaining each of the 100 possible outcomes is exactly .01.

My objection to the D66 is inaccuracy. It has a maximum result of 66, but it doesn't have 66 outcomes (or theoretical 'sides')

The Prophet.

Simulating a D66 with one 10-sider and one 6-sider is easier

That combination will only get you to 60.

nobody uses the bottom six options anyway - they always beg to reroll it...

Here's another useless fact - the sum of the pips on both sides of the die should always be 7 - ie 1 is opposite 6, 3 is opposite 4, 2 is opposite 5. This holds true for all types, afaik.

It's a convention, but not universally held-to, that the opposing faces on any die that has opposing faces should total one more than the highest number on the die. I've known dice where it didn't, and the D4 of course just doesn't work that way, since you read either the point or the bottom edge, depending on the die in question.

The Prophet.

There are actually systems that use that? Blimey, I might have to dig mine out.

One of my friends has a D7, that's quite wierd. Two of the sides are pentagons, the other five are rectangles, so it's roughly cylindrical. We've tried rolling it lots, and it seems to be fair, despite the different shapes.

Bez

There’s also a three sided dice, which looks similar to an American football in shape. It has three sides and is pointed at the ends. I’m not sure the purpose of this though, since you can just use a 6 sided die and call 1&2 1, 3&4 2 and so on.