Hello and Welcome to another development diary for Europa Universalis IV. This time we take a look at a concept that neither we nor you have not been entirely happy with in any previous Paradox game: Espionage.
In the next major patch, we have completely reworked how espionage works. No longer is every spy action done by just sending a diplomat that will perform the action for as long as it is there, but now there is a concept of spy networks.
You now send a diplomat on a mission to a country to build up a spy network. The network can reach up to 100% power, and that power can be used to execute spy actions, such as sow discontent, fabricate claims, etc.
Spy Offense has been renamed to Spy Network Construction, and determines how quickly you build spy networks in another nation.
Spy Defence has been renamed to “Foreign Spy Detection”, and now determine the chance of detecting hostile network buildups and disrupting it. A disrupted network will lose some of its power, and also make it impossible for you continue improving it for a time period.
Performing an action is instant, and as long as you have the power, success is automatic. However, networks that are not actively built will slowly decay.
You can also target other nations networks with counterespionage, to actively reduce their capabilities of their network.
There are three passive benefits to having a strong spy network in another nation. First of all, if you have the Cossacks expansion and picked the Espionage Ideas, you have access to Study Technology, which is no longer a source of power, but instead a possibility to reduce technology costs by up 30% from having networks in nations ahead of you (the size of the discount depends on how far ahead they are in each tech). Secondly, the new expansion grants up to 20% higher siege ability against nations where you have a spy network. Finally, the new expansion gives you up to 10% less AE in that country.
Of course, all of those scale with the power of the spy network.
Espionage now contains the following actions.
Fabricate Claim: Gives you a claim on an eligible province for a low cost.
Justify Trade Conflict: Gives you a trade conflict CB if conditions are applicable for a low cost.
Support Rebels: Selected rebel faction gets +10% chance to progress towards revolt each month for 5 years for a very high cost. It will also cost a fair amount of cash to support ythe troops.
The following requires the Espionage Ideagroup.
Sow Discontent, applies +3 unrest and reduces legitimacy, republican tradition, devotion or unity for 5 years for a high cost
Infiltrate Administration: Lifts Fog of War over the target country for 5 years for a medium cost.
Sabotage Reputation: -3 diplomatic reputation for 5 years for a medium cost.
Agitate for Liberty: Selected subject has +25 liberty desire that lasts 5 years for a high cost.
There is also four new actions enabled by the new expansion, two of those we’ll tell you about here, two others are for future development diaries.
Sabotage Recruitment: Gives 20% less manpower and Sailor recovery speed for 5 years for a medium cost.
Slander Merchant: Reduces Global Trade Power by 33% for 5 years for a high cost.
Of course actions that require previously expansions will still require those expansions.
Next week we’ll be back with a look at Africa.
In the next major patch, we have completely reworked how espionage works. No longer is every spy action done by just sending a diplomat that will perform the action for as long as it is there, but now there is a concept of spy networks.
You now send a diplomat on a mission to a country to build up a spy network. The network can reach up to 100% power, and that power can be used to execute spy actions, such as sow discontent, fabricate claims, etc.
Spy Offense has been renamed to Spy Network Construction, and determines how quickly you build spy networks in another nation.
Spy Defence has been renamed to “Foreign Spy Detection”, and now determine the chance of detecting hostile network buildups and disrupting it. A disrupted network will lose some of its power, and also make it impossible for you continue improving it for a time period.
Performing an action is instant, and as long as you have the power, success is automatic. However, networks that are not actively built will slowly decay.
You can also target other nations networks with counterespionage, to actively reduce their capabilities of their network.

There are three passive benefits to having a strong spy network in another nation. First of all, if you have the Cossacks expansion and picked the Espionage Ideas, you have access to Study Technology, which is no longer a source of power, but instead a possibility to reduce technology costs by up 30% from having networks in nations ahead of you (the size of the discount depends on how far ahead they are in each tech). Secondly, the new expansion grants up to 20% higher siege ability against nations where you have a spy network. Finally, the new expansion gives you up to 10% less AE in that country.
Of course, all of those scale with the power of the spy network.
Espionage now contains the following actions.
Fabricate Claim: Gives you a claim on an eligible province for a low cost.
Justify Trade Conflict: Gives you a trade conflict CB if conditions are applicable for a low cost.
Support Rebels: Selected rebel faction gets +10% chance to progress towards revolt each month for 5 years for a very high cost. It will also cost a fair amount of cash to support ythe troops.
The following requires the Espionage Ideagroup.
Sow Discontent, applies +3 unrest and reduces legitimacy, republican tradition, devotion or unity for 5 years for a high cost
Infiltrate Administration: Lifts Fog of War over the target country for 5 years for a medium cost.
Sabotage Reputation: -3 diplomatic reputation for 5 years for a medium cost.
Agitate for Liberty: Selected subject has +25 liberty desire that lasts 5 years for a high cost.
There is also four new actions enabled by the new expansion, two of those we’ll tell you about here, two others are for future development diaries.
Sabotage Recruitment: Gives 20% less manpower and Sailor recovery speed for 5 years for a medium cost.
Slander Merchant: Reduces Global Trade Power by 33% for 5 years for a high cost.
Of course actions that require previously expansions will still require those expansions.
Next week we’ll be back with a look at Africa.