Formulas & References

Every numeric field in the Rules Builder (a Stat Bonus's Bonus, an Armor Class rule's Formula, a Charge Pool's Max charges) accepts more than a plain number. You can write a formula that reads values off the character, so the effect scales automatically as they grow.

• A plain number: 2
• A reference: @level
• A mix: @will + 1
• Dice, in fields that support them: 1d6

The reference vocabulary

References start with @ and are filled in from the character carrying the item. For player characters you can use:

Reference	Value
@level	Character level.
@strength, @dexterity, @constitution, @intelligence, @will	The character's stat modifiers.
@key	The highest modifier among the character's class key stats, handy for class features that should work for every subclass build.
@strengthSave, @dexteritySave, @intelligenceSave, @willSave	Saving throw modifiers.
@arcana, @examination, @finesse, @influence, @insight, @lore, @might, @naturecraft, @perception, @stealth	Skill modifiers.

You can also reach any value on the sheet by its full path, such as @attributes.hp.max or @attributes.movement.walk. On NPCs and monsters the shortcuts above are mostly unavailable. Stick to plain numbers or full paths for monster features.

Formulas support basic math (+, -, *, /, parentheses) and rounding helpers: floor(@level / 2) gives half the character's level, rounded down.

WARNING

An empty formula counts as 0. A formula the system can't understand shows an "Invalid roll formula" warning and the rule contributes nothing. See the debugging tips below.

Numbers vs. dice

Most rule fields need to settle on a single number the moment the sheet recalculates: a stat can't be "3 and a half, sometimes". In those fields, write plain numbers or references; if you sneak dice like 1d6 into them, the dice are skipped and count as 0.

The exception is the Damage Bonus rule. Its Bonus field recognizes dice notation and keeps it as dice: the 1d6 is appended to the damage roll and rolled fresh on every attack. Anything without dice in it (2, @level) is resolved to a flat number and added to damage instead.

Worked examples

+1 damage per level (a Standard of the Legion boon that scales with the bearer):

• Rule: Damage Bonus · Bonus → @level · Delivery → melee · Source → weapon

+Will modifier to spell damage (an Archmage's Focus wand):

• Rule: Damage Bonus · Bonus → @will · Source → spell

+1d6 fire damage (a classic Flametongue sword):

• Rule: Damage Bonus · Bonus → 1d6 · Damage type → Fire · Delivery → melee · Source → weapon

Charges that scale with your key stat (a class feature with @key + 1 uses of its power):

• Rule: Charge Pool · Max charges → @key + 1

Debugging a formula

1. Watch for the warning. "Invalid roll formula" pops up when the sheet recalculates a broken formula. Check for typos like @leve or an unclosed parenthesis.
2. Test with a plain number first. If 2 works but @will doesn't, the reference is the problem.
3. Mind who's carrying the item. @level and stat references resolve on the character the item sits on. On a monster, most shortcuts resolve to nothing.
4. Dice doing nothing? You've probably used dice in a field that needs a single number. Only Damage Bonus rolls dice; everywhere else, replace 1d4 with a flat value or a reference.

Related pages

• Rules Builder Basics
• The Condition Box
• Rules Reference: Bonuses
• Rules Reference: Resources