Numeric Dice
GM (Game Master): Okay, Welcome to the game. Let’s get started. You’ve just received a contract to explore a nearby dungeon. Roll a d5 and it’ll take that many days.”
Grindon the Brave: “d5”
GNOLL: 3
GM: Okay, you should have enough supplies for that trip. Saddle up and let’s go!
Grindon the Brave: Onward to adventure! I’ll pick up a book in the store to read on the road!
GM There’s a few book shops around here, That’ll be 2d4 gold pieces when you eventually find an interesting one
GNOLL: 7
Grindon the Brave: “Ugh. Expensive, but it is a signed copy at least!”
GM: You catch the next wagon out of town and buildings start changing into fields of wheat and barley as it moves out. The journey is long and… “z4”
GNOLL: 0
GM Uneventful! You make it to the dungeon unabated. However, at the entrance stands.. d{2,4,5}
GNOLL: 2
GM Two goblins! Dressed up in rusted armour and bent weaponry, as if protecting the entrance.
What will happen next? Continue to the next chapter!
Basic Numeric Dice
The basic form of a dice roll is xdy where x, y ∈ ℤ+.
In plain english, this means that x and y are positive whole numbers (e.g. 1, 7, 138).
The value x is the number of dice that you wish to roll. You can exclude this, and it’ll be assumed you mean a single die.
The value y tells us how many sides the dice has. A regular six-sided die can be called a “d6”. You can’t exclude this value, because we won’t be able to tell how many sides the dice has!
Numeric Dice Examples
1- A Constant Value. It will just return the value “1”1d4- A Single Die Roll with 4 Sides. It will return a value between 1 and 4.d4- This is the same as above, as x is assumed to be 1.2d4- Roll 2 Dice with 4 Sides. It will return a value between 2 and 8.d- This will return an error because there is no y term.
The xdy notation is one aspect of dice notation that is common for almost every application, so we don’t have to make any choices here!
D without y (as seen in the last example) can default to a set number of sides if a game system only uses one type of dice. However, this default can change between games so as a generic notation we do not assume a value.
Zero Bias Notation
It is assumed that the values on a dice start from 1. (e.g. a d6 dice would have values 1,2,3,4,5,6). Zero-Bias notation allows your dice to start from zero instead (e.g. z6 would have values 0,1,2,3,4,5).
Rolling behaviour is identical to using ‘d’ for symbolic dice.
There is inconsistency in various dice notation on how to represent zero-bias notation.
Alternative representations include using a minus sign ref (i.e. d-6) but we consider this non-obvious as it could easy mean values from -1 to -6.
It also conflicts with systems that have only one die and abbreviate from e.g. 2d6 to just “2d”
Customizable Numeric Dice
In the case where you need non-standard die sides (that do not start from 0/1, or do not regularly increment by 1), a custom dice can be made specifying the allowed values in braces.
A simple prime number dice might look like d{2,3,5,7,11,13}.
Where numbers are all consecutive, one can use a hyphen to indicate a range e.g. a die with sides 10,11,12,13,14,15 could be written as d{10..15}. This notation includes both the given start and end values in the pool of rollable values.
Customized Dice Examples
- d{} - produces an error for a die with no sides is not a die at all
- d{1,3..6} - produces a value between 1 and 6, but excluding 2
With more complicated dice, brings more complicated syntax. However, we want to keep the syntax as straightforward as possible.
We note however that there are sometimes easier ways to do these dice if you think about them. e.g. the latter dice could be represented as d6+9
We choose .. instead of - to avoid confusion with minus math