Hoi4 modding Wiki

the .txt and .yml files, within your project folder, are written in data file format.  when hoi4 launches, it reads these data files to create the game rules and the playboard that go with hoi4. The Keywords mentioned here are naming conventions used to refer to a value or group of different values that the compiler recognizes. To learn more which values are accepted, visit the tag's page.


Four fixed lists of keywords are known that you must understand to recognize how things are structured within the data files. I've categorized them as follows : 

  • Effects : There is a specific list of effects that can instantly change the game. Effects are carried out once when triggered by the rules around it. Most notably, the completion reward of all focuses are effects.
  • Modifiers : The modifier list is a list of different numeric value that can be referred to and modified. They represent the strengths of a country and are mostly changed by ideas.  
  • Operators : The operators are a special list of characters and keywords that are used in many placed to represent certain arithmatic ideas. The easiest to understand example is the equals (=) sign, that denotes value assignment.  
  • Triggers : The triggers are a fixed list of questions you can ask the game, to which the answer will be yes or no / true or false. triggers are used to set conditions for effects or modifiers, for example to check if focuses are unlocked, or the likelihood for an ai to do something.  

Data Types

The following data types are recognised within Hearts of Iron IV modding. Data types are used to write down static values within the game.