- For general graphics and other game adjustments, see 設置.
When starting a new game, there are a number of options that can be configured to adjust the campaign experience. Note that the game configuration cannot be changed once a campaign has been started.
難度
Different difficulty settings adjust the overall difficulty of the game by granting bonuses or maluses to player or AI nations, as well as adjusting AI aggressiveness. On the default setting, Normal, no nations will get bonuses and all countries will play the same.
| Very Easy | Easy | Normal | Hard | Very Hard | |||
|---|---|---|---|---|---|---|---|
| Player modifiers |  Population Happiness
|
+15% | +10% | - | - | - | |
 National Manpower
|
+50% | +25% | - | - | - | ||
 Monthly Ruler Popularity Gain
|
+1 | +0.5 | - | - | - | ||
 Morale of Armies
|
- | - | - | - | -10% | ||
 Morale of Navies
|
- | - | - | - | -10% | ||
| AI modifiers |  National Tax
|
- | - | - | +25% | +50% | |
 Provincial Loyalty
|
- | - | - | - | +0.01 | ||
 Integrated Culture Happiness
|
- | - | - | +10% | +15% | ||
| Morale of Armies
|
-15% | - | - | +5% | +10% | ||
| Morale of Navies
|
-15% | - | - | +5% | +10% | ||
| National Manpower
|
- | - | - | +25% | +50% | ||
 Aggressive Expansion Change
|
- | - | - | - | -0.02 | ||
| Monthly Ruler Popularity Gain
|
- | - | - | +0.5 | +1 | ||
 Monthly Tyranny
|
- | - | - | -0.02 | -0.04 | ||
 Threshold for Civil War
|
- | - | - | +5% | +10% | ||
| Aggressiveness | Reduced | Reduced | - | Increased | Increased |
Note that on hard and very hard, AI bonuses are multiplied by 1.25 or 1.50, respectively, for antagonist nations. This means, for instance, that an antagonist nation will get a +75% National Tax bonus on very hard instead of the +50% for other AI nations.
Ironman mode
Ironman mode is an optional gameplay flag that can be enabled to restrict control over the savegame, preventing the player from correcting mistakes and changing decisions made during the course of play. Playing in Ironman is required to unlock achievements; however, it is also possible to play in Ironman and not be eligible to unlock achievements if the checksum is changed, which can happen if playing with a mod that changes the checksum (broadly, any mod that changes gameplay in some way) or if debug mode is enabled.
Playing in Ironman mode has the following restrictions:
- Only a single save is stored, which is overwritten on every new save; it is thus impossible to load an earlier save if something goes wrong (unfortunately, this includes save game corruption), unless manually backed up.
- The game saves automatically every 3 months (at the beginning of every January, April, July, and October) and on quitting. Saving manually is still allowed at any time.
- Save files can be stored in the Steam Cloud or on a local drive, but are encrypted and cannot be edited.
- Most console commands are disabled.
Mixed gender rules
The Mixed gender rules toggle controls whether or not gender equality can be toggled over the course of the game. Countries with gender equality treat women and men equally, allowing women to be appointed to 
positions and be elected or inherit the throne as 
ruler, while countries without gender equality are male-dominated and block women from most political roles (though they may still be able to succeed to the throne in monarchies depending on the succession law).
By default, gender rules are static, which means that whether or not a country has gender equality is predetermined at the beginning of the game and cannot be changed (with most countries being male-dominated). Selecting the toggle and enabling mixed gender rules will make the Gender Equality decisions available ingame, allowing countries to embrace or abolish social equity and change the status of gender equality in their realm more or less freely. Note that just enabling the Mixed gender rules toggle does not have any effect in of itself - only by taking the decisions will there be any difference from static gender rules. The AI will also never take the gender equality decisions, which means that the mixed gender rules are essentially a player-only option.