Dice

Dice show up in three places in Rollplay. They are all written the same way, but each one does a different job:

	What it does	Example	Where it's used
Dice Roll	Rolls dice and gives a result	d20 + x, [d20 + DEX]	Every time a Player taps an attribute, or a roll written in a Macro
Dice Formula	Builds a Dice Pool. Nothing is rolled.	[Level]d8	A Dice Pool's formula or default value
Dice Operator	Reads a number out of a Dice Pool	max({Hit Dice})	Any numeric Formula

A Dice Pool is an attribute made of dice, like Hit Dice or a Luck Die. See Attributes for how they work on the character.

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Writing Dice

Dice are written in the standard NdS format, where N is the number of dice and S is the number of sides:

2d6 - two six-sided dice
d10 - one ten-sided die
2d6 + d10 - two d6s and a d10
d8 + 4 - one d8, plus a fixed bonus of 4

You can combine multiple Dice Pools by referencing them directly in a formula:

{Weapon Damage} + {Bonus Damage} - adds two dice pools together

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Dice Rolls

A Dice Roll is dice actually being rolled, with a result at the end. Players roll every time they tap an attribute, and every time they tap a roll written in a Macro, like [d20 + DEX].

Modifiers

Modifiers change how dice are rolled. They work everywhere dice are written: in rolls, in Macros, and in Dice Formulas.

Explosive, Reroll, Reroll Once and Count all accept the same comparisons.

Success Checks

Add a comparison after a roll, and the result is checked against a Formula at the moment you roll. The roll then succeeds or fails instead of only giving a number.

d20 < x + INT - roll a d20, and succeed if the result is less than the attribute's value plus INT
d20 + x >= 15 - roll a d20, add the attribute's value, and succeed on 15 or more

Attribute Rolls

The Creator decides what happens when a Player taps an attribute. In these rolls, x is the value of the attribute being rolled, and nothing else.

Default Roll

The Default Roll applies to every attribute that doesn't have a Custom Roll of its own. It's optional, and can be left empty.

Custom Rolls

Any attribute can have a roll of its own, set in its Roll field, which replaces the Default Roll for that attribute. Custom Rolls use x, Modifiers and Success Checks the same way:

2d20kh1 + x - roll two d20s, keep the higher one, and add the attribute's value
d20 < x + INT - roll a d20, and succeed if the result is less than the attribute's value plus INT

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Dice Formulas

Dice Formulas produce a Dice Pool.
They are used wherever you need to define or compute a Dice Pool dynamically, such as Hit Dice, Weapon Damage, or Spell Damage.

Dynamic Dice with Macros

Often, you want a dice expression where the number of dice or the dice size depends on an attribute.
You can't write Strength * d10 — that would try to evaluate everything as a number.

Instead, use a Macro: wrap a formula in [ ] to evaluate it to a number first, and then use it as part of the dice expression.

Conditional Dice

You can use the conditional operator to choose between different Dice Pools:

Tired > 0 ? {Exhausted Die} : {Rested Die}
If the character's Tired attribute is above 0, use their Exhausted Die pool; otherwise use the Rested Die pool.

This works because when a formula references a Dice Pool, the result is itself a Dice Pool.

Default Values for Dice Pools

You can use a formula to set the default value of a Dice Pool.
A common use case is initializing current dice from a maximum:

Default Value for Hit Dice: {Max Hit Dice}
This ensures a character's Hit Dice start equal to their Max Hit Dice.

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Dice Operators

Dice Operators let you extract a numeric value from a Dice Pool.
This is useful when you need a number derived from a Dice Pool, rather than the pool itself.

They share their names with the Functions you use on numbers, but do something different when given a Dice Pool: count(Skills) counts the Skills that aren't zero, while count({Hit Dice}) counts the dice in the pool.

min({Hit Dice}) - the minimum the pool can roll (also equals the number of dice, since each die rolls at least 1)
max({Hit Dice}) - the maximum the pool can roll (e.g. 4d8 returns 32)
avg({Hit Dice}) - the average roll, rounded up
roll({Hit Dice}) - a random value, rolled on the spot
count({Hit Dice}) - the number of dice in the pool

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