Living Rules Reference · v2.0
56
Modifiers
A modifier is a number that is applied by an ability to increase or decrease the attribute values of a unit or the results of a die roll.
A modifier is always preceded by the word “apply” followed by a numerical value.
A modifier value preceded by a “+” is added to the attribute or result being modified; a modifier value preceded by a “-” is subtracted from the attribute or result being modified.
Source: Twilight Imperium: Fourth Edition — Living Rules Reference v2.0 (September 22, 2020), page 23. Rules text reproduced verbatim; the rulebook’s diagrams are omitted.