Spies

This article is accurate for the latest versions of EU3, Napoleon’s Ambition, In Nomine, Heir to the Throne and Divine Wind.

Spies are agents used for sabotaging rivals. They can be used in an opponent's provinces to spread disorder, foment rebellion, and even reveal the fog of war. As with other agents, a maximum pool of 5 can be attained at a time.

Number of Spies

The number of Spies gained per year is dependent on the following factors:

Base: 0/year
Domestic Policy:
- Mercantilism: up to +1/year
- Plutocracy: up to +2/year
National Ideas
- Espionage: +1/year
College: +0.05/year per College built

Spy mission chance

The likelihood of a Spy succeeding or being detected during a mission depends on the Spy Efficiency of the attacker and the Spy Defence of the target province (as well as the difficulty of the mission itself). Being detected results in a loss of prestige, grants the target a "Spy Discovered" Casus Belli, and damages relations between the two nations; certain missions also increase infamy when detected.

The following factors impact the effectiveness of Spies:

Domestic Policy:
- Centralisation: up to +25% Defence and +5% Efficiency (Decentralisation results in up to -25% Defence and -5% Efficiency.
- Free Subjects: up to +12.5% Defence (Serfdom results in up to -12.5% Defence)
- Narrowminded: up to +10% Defence
- Mercantalism: up to +20% Defence (Free Trade results in up to -20% Defence)
Ruler's Diplomacy skill: +1% Efficiency per level
Advisors
- Inquisitor: +4%/level to Defence
- Spymaster: +2%/level to Efficiency
National Ideas
- Espionage: +10% to Efficiency
Prestige: up to +10% to Defence (-10% at -100 Prestige)
Stability: up to +15% to Defence for maximum Stability (-15% at -3)

Locally, the Government line of buildings can positively impact Spy Defence.

Spy missions

There are two types of missions: capital-only and province missions. Capital only missions are only available in the capital province of the target and will result in a nation-wide effect, while province missions can be executed in any province of the target, and the effects of its success are only for that province.

Capital-only missions

Mission	Cost	Difficulty	Prestige loss	Infamy gain	Additional Requirements	Effect
Fabricate claims	100	2	1	1	Target is monarchy, is in same religion group as you, isn't in a personal union, target's ruler has a Legitimacy lower than 50 OR has a regency with an heir's claim lower than 33. You must be a monarchy and not be the lesser partner in a personal union.	Gives the Obscure Documents Casus Belli on the target nation.
Spy ring infiltration	10	2	0	1	Target nation does not already have the 'Spies infiltrated' country modifier.	The target nation gets the 'Spies infiltrated' country modifier for 120 days. During this period, the target's spy efficiency is reduced by 25%.
Incite against merchants	25	2	1	0	Target nation does not already have the 'Despised merchants' country modifier.	The target nation gets the 'Despised merchants' country modifier for 120 days. This modifier reduces the target's trade income by 25%.^[1]
Weaken rival league	25	3	1	0	You are a merchant republic, target nation is not a merchant republic but is in a trade league.	The diplomatic relationship between the target nation and its league leader is reduced by 25 points.
Tarnish reputation	25	3	2	0	Target nation has a Prestige of 0 or more.	Target nation loses 10 Prestige points.
Infiltrate administration	20	2	1	0	Target nation is not already infiltrated.	The player can see everything the target nation can see for 36 months.
Sow discontent	100	5	5	0	Government Tech level 6, target nation does not already have the 'Discontent' country modifier.	The target nation gets the 'Discontent' country modifier for 365 days. During this perod the stability cost for the target nation is increased by 50%.
Sabotage reputation	200	8	2	1	Target nation's Infamy is at least 20% of its Infamy limit.	The target nation's Infamy increases by 1 point.
Counterfeit currency	100	4	1	1	Government Tech level 23.	The target nation's inflation increases by 1%.
Assassinate advisor	50	5	1	1	Target nation has at least 1 advisor.	One of the advisors of the target nation dies.
Damage Shogun's influence	45	6	2	1	You must be a Daimyo and not the Shogun. The target nation is the Shogun.	The target nation loses 5 Imperial influence.
Tarnish relations with Shogun	25	2	1	0	Both you and the target nation must be Daimyos and neither is the Shogun.	The diplomatic relationship between the target nation and the Shogun is decrease by 30 points.

Legend:

Mission: the description of the mission.
Cost: how much gold the mission costs.
Difficulty: a number between 1 and 10 that determines the success chance of the mission. A higher value means a lower chance of success.
Prestige loss: how much Prestige is lost when the mission is detected.
Infamy gain: how much Infamy is gained when the mission is detected.
Additional requirements: what is needed to be able to execute the mission.
Effect: what happens when the mission is successful.

Province missions

Mission	Cost	Difficulty	Prestige loss	Infamy gain	Additional Requirements	Effect
Commission privateer	25	2	1	0	The Pirates must have Naval Tech 9. Your nation cannot have the 'Anti-piracy act' modifier. Your nation cannot be in the Sub-saharan or New World technology groups.	Creates a pirate in a neighbouring sea province.
Bribe defenders	25	2	0	0	Target province is under siege.	Increases the siege progress by 20%.
Support revolt	25	1	1	0	Target province does not already have the 'Foreign support for rebels' province modifier.	The target province gets the 'Foreign support for rebels' province modifier for 360 days. During this period, the target province's revolt risk is increase by 3%. Additionally, there is a 45% chance of getting a revolt and 5% chance of a big revolt.
Incite natives	25	1	1	0	Target province is a colony, there are at least 100 natives in the target province.	Creates a native uprising in the target province.
Incite troop desertion	25	2	5	0	Target province does not already have the 'Troop desertions' province modifier.	The target province gets the 'Troop desertions' province modifier for 60 days. During this period the support limit of the target province is lowered by 5 and its maximum attrition is increase by 5%
Sponsor patriots	100	3	5	0	Target province can spawn Patriot rebels	Patriot rebels that are friendly to you will spawn in the target province. The rebels will be the same unit types your country uses for your own military. This can overwhelm countries quite easily if their land tech is extremely inferior to yours, making them useful if you are at war with an island nation and you lack a strong navy.
Sponsor nationalists	100	3	5	0	Target province can spawn Nationalist rebels	Nationalist rebels that are friendly to you will spawn in the target province. The rebels will be the same unit types your country uses for your own military. This can overwhelm countries quite easily if their land tech is extremely inferior to yours, making them useful if you are at war with an island nation and you lack a strong navy.
Sponsor pretender	100	4	5	1	Target nations is either in a regency OR has negative stability.	Pretender rebels that are friendly to you will spawn in the target province. The rebels will be the same unit types your country uses for your own military. This can overwhelm countries quite easily if their land tech is extremely inferior to yours, making them useful if you are at war with an island nation and you lack a strong navy.
Sponsor heretics	100	2	3	1	Target nation's religion is in your religion group, target province's religion has your religion, target province's religion is different from the target nation's religion.	Heretic rebels that are friendly to you will spawn in the target province.
Forge claim on Daimyo	50	3	5	2	You must be a Daimyo but not the Shogun, target province does not have your core.	You gain a core on target province, you gain 5 Infamy, diplomatic relation between you and the Shogun is lowered by 50.
Shogun's Forge claim on Daimyo	50	3	1	3	You must be the Shogun, target province does not have your core.	You gain a core on target province, you gain 5 Infamy, you lose 5 Shogun influence.