(4-21) Proposal: Espionage - Rework of Mission Duration Modifiers

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Jul 24, 2022
The intention of this proposal:
  • Make defense against enemy spies more controllable for the player and more relevant. Increase the value of buildings like Constabularies and of Counterspies.
  • Fix several issues with the current espionage mission duration modifiers, including:
    • The modifiers for tech/policy difference (intended to make spy missions against technologically/culturally superior civs shorter) are not in all cases applied.
    • England's UA leads to English Cities being more vulnerable to enemy spies than the cities of other civs at the beginning of Renaissance (because the star rating of English cities decreases from turn 1 on, while it's constant at max value for all players without spies)
    • Mission Durations are reduced on Quick Game Speed, but aren't increased on Epic and Marathon Speed.
    • An additional spy level (or England's UA bonus) decreases mission durations by only an insignificant 6%
Please see the following thread for a detailed description of how the current modifiers work and an explanation why constabularies are not very valuable currently: https://forums.civfanatics.com/threads/ideas-how-to-improve-the-espionage-system.682753/


Each mission has a mission-specific Base Duration B. It is modified by a Game-Speed Modifier GS to obtain the Standard Duration S.

S = B*GS

The mission duration is calculated by applying three percentage modifiers to the Standard Duration: Spy Power SP, City Security CS, and Empire Difference ED.

Total Mission Duration = S*(1 + SP + CS + ED)

The Total Mission Duration is capped between 50% and 150% of the Standard Duration.

The values used:

B (Base Duration)
: Changes to the base durations are not part of this proposal, as it focuses on the duration modifiers. For reference, the currently used values are listed below.
Spoiler Base Durations :


GS (Game-Speed Modifier): (67% / 100% / 150% / 300%) for (quick / standard / epic / marathon). These are the usual duration modifiers for game speed that are also used in many other contexts, like growth or research costs. For example, a siphon mission (base duration 30) will have a standard duration of 20/30/45/90 Turns.

SP (Spy Power): Spy Power is a negative modifier, so it decreases mission durations by the specified percentage value. Spy Power is (0% / -25% / -50%) for Spies of Level (1 / 2 / 3). Note that English spies operate 1 level higher, so their missions will be 25% quicker.

CS (City Security): City Security is the star rating of the city that's shown in the espionage screen, with values between 0% and +50%. City Security is +25% for all cities before the first player has reached Renaissance. After that it changes gradually each turn using the following modifiers:

Spoiler :

-0.04 per population
-0.1 per excess unhappiness
+0.01*(City Strength)
+0.1 per Public Work
+1 for a Counterspy
+0.25 for England
+0.5 for Defense Process
+0.34 from Social Policy "Empiricism" (Rationalism Branch)
+0.5 for Constabulary, Wat, Police Station, Military Base. +0.15 for National Intelligence Agency, +0.75 for Great Firewall

ED (Empire Difference): This modifier is based on the difference in the number of policies and technologies between the spy owner and the targeted civ. Spy Missions are quicker against technologically/culturally superior civs, and slower against inferior ones. It's calculated as 4% * (Difference in Number of Policies), capped between -20% and 20%. Additionally 4% * (Difference in Number of Techs), capped between -20% and 20%. So, if a spy is send against a civ with 2 more policies and 3 more techs than the spy owner, mission durations are reduced by 20%.

EDIT: Proposal amended: Changes to espionage buildings removed. Previous spy missions modifier removed. Proposal rewritten to make it clearer. Minor changes to some values.
Spoiler The first version of this proposal :

The proposed rework of mission durations:
  1. The (mission-specific) base mission durations are directly modified by game speed using the usual duration modifiers (67/100/150/300 for quick/standard/epic/marathon). For example, a siphon mission will then have a base duration of 20/30/45/90 Turns. This will make espionage much more homogeneous across game speeds.
  2. To the base mission duration four percentage modifiers are applied: Spy Power is based on the rank of the spy and reduces mission length (between -25% and -50%, higher values for England). City Security is the star rating of the city (between +5 and +50%) and increases mission length. Empire Difference is based on the difference in the number of policies/techs between spy owner and targeted civ (between -40% and +40%). It makes spy missions quicker if the targeted civ is ahead and slower otherwise. Previous Spy Missions is a modifier that increases mission length for each previous mission that has been performed by the civilization in the city (between 0% and 25%).
  3. Spy Power is calculated as follows: 25 Base Value. +50% for each Rank the Spy is above the first rank and +50% for England (both values increased from 25% to 50% because the current modifiers of 25*0.25 = 6% are very low). The currently existing +25% Bonus for Open Borders is removed, as it is an incentive to spy on your friends rather than your enemies.
  4. City Security is fixed at the value of 25 for all cities before the first player has reached Renaissance. Currently, it is constantly at max value if a player has no spies themselves and is not being spied on, which punishes England and players with the Statecraft policy because the Security Level of their cities can decrease while it's kept at max value for most other cities.
  5. City Security changes each turn after the first player has reached Renaissance, but it does so much more gradually than currently. It's also no longer reset to the maximum value after an enemy spy mission is completed. This makes city security more of a long-term investment: If it's low, enemy spies will continuously be able to perform spy missions more quickly. If it's high, it will provide a more solid protection than it does now. This increases the value of counterspies and make it more important to build the buildings in the Constabulary line.
  6. City Security can be increased over time by having a high city strength or working the Defense Process. The Constabulary building line is extended from currently 3 buildings (Constabulary - Police Station - Military Base) to 4 buildings. The National Intelligence Agency is removed and turned into a regular building (Rationale: The bonuses of the NIA overlap with Bletchley Park. Also, almost all of them are empire-wide bonuses, making it an uninteresting national wonder as it doesn't matter which city it's built in.)
  7. The Empire Difference modifier is calculated as: +-4% for each policy, +-4% for each tech, both capped at +-20%.
  8. The Previous Spy Missions modifier is calculated as the square of the number of previously completed missions against the city, capped at 25%

These modifiers are a compromise between modifiers that are controllable by the player and reward investment into spies/counterespionage, and modifiers that ensure espionage is to some extent a catch-up mechanic as it was in the base game.

The details of parts (5) and (6) of the proposal
The modifiers to City Security Level per turn:

  • -0.04 per population
  • -0.1 per excess unhappiness
  • +0.01*(City Strength)
  • +0.08 per Public Work
  • +1 for a Counterspy
  • +0.5 for Defense Process
  • +0.2 from Social Policy "Empiricism" (Rationalism Branch)
  • +0.2 for each building in the Constabulary Line (see below)

The buildings in the Constabulary Line:

Constabulary renamed to Guardhouse.
New Building: Constabulary (Scientific Theory). Production and Maintenance Costs as Public School. -1 Unhappiness from Distress and -1 Unhappiness from Illiteracy.
Police Station: Moved to Electricity. Production and Maintenance Cost adapted to match the costs of the Hospital. -1 Unhappiness from Distress and Poverty. As before: When you successfully counter a foreign Espionage action in this city, gain 25 Culture and 25 Gold, scaling with Era and Level of the foreign Spy.
New Building: Intelligence Agency (Electronics). Production and Maintenance Cost of the current Police Station. -1 Unhappiness from Distress and Boredom. +10 Gold and Science in this City when you successfully complete a Spy Mission in a foreign City, scaling with Era.

National Intelligence Agency: removed
Changes to the Social Policy "Shadow Networks" (Statecraft): Now gives +2 Science to each of the 4 buildings above (was +3 Science to Constabularies and Police Stations)
Changes to Military Base: Remove increase of Spy Resistance.
Changes to "The Motherland Calls": Now provides a free Intelligence Agency (was a free Police Station).
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Ok while it seems like a lot going on here, its actually pretty straightforward all said and done. In Formula turns (for standard speed): Base Mission Duration = 30 * (1+ City Security + Previous Mission + Spy Power + Empire Difference).

That said, I do have some critiques:

  • Spy Power should be 0%, -25%, -50%. I think its silly that even base level spy's lower duration, that's just weird added math. Best to just start at 0 and go from there.
  • The previous spy mission modifier is so low it might as well not even exist. If I've done 3 previous missions in a city that's 9%. 9% of 30 turns is 2.7 turns..... which is still less than the time it takes to move and setup a spy somewhere else.
  • There needs to be a modifier based on mission type. A gold steal taking 20 turns is one thing, a mission to knock down city defenses taking 20 turns is way too long.
  • I think its a mistake to make city strength a part of the modifier. The goal should be to reward players that invest in spy defense, not getting city strength because they need city strength anyway. I build walls because I need walls not to keep out spies. I use defense as an emergency (oh god I need help) lever, it should not be a thing I actually use because I can't keep out spies otherwise. Just make this the constabulary line strong enough to do the job, and let people who invest in those buildings reap the benefits.
    • I am fine with the Military Base adding to this, mainly because it already does in the current version, and because its often "overkill" as a security building, so this niche seems appropriate.
  • if you want to add a new building I think that should be a seperate proposal. I worry that a good core would be overshadowed by those who don't want more buildings in the game.
Game balance is important, and the current spy system simply does not account for this.

I play on Emperor - Epic speed as you all know, and not reloading after a spy dies from failing a coup is just not an option. For me, at the start of each turn, each "coup" button has already been set to either fail or succeed, based on the percentages, but those never go above 51% for me (so the 100% possibility is probably bugged)

The advantage is I get to have a city state as ally for a few turns, until someone else uses one of their hundred great diplomats they got lying around. But at the cost of diplomatic penalty, so it's still very much balanced.

And the fact that reloading doesn't actually change these start-of-turn-predetermined outcomes means that I can't rely on couping 3-4 city states every turn like before (If I have 3-4 spies)
While I like the idea of extending Espionage buildings to make spy defense more useful, I dislike taking NIA down and replacing it with the Intelligence Agency.

Because in real life, each nation has its own NIA, you know like the CIA. It would be weird if each city has its own intelligence agency.
I rather keep NIA but still add a new building called Cyber Security, because it makes sense since your local police station probably has a cyber security team of its own.

Also, then there are no late national wonders since National Visitor Center is also replaced by Interpretive Center.
The changes to the buildings are not intended to be the main part of the proposal. As they are controversial and also unnecessarily bloat up the proposal, I will amend the proposal and remove them, keeping only the modifications to the Spy Resistance values of the buildings/policies.
Spy Power should be 0%, -25%, -50%. I think its silly that even base level spy's lower duration, that's just weird added math. Best to just start at 0 and go from there.
I've taken that from the how it is in the current version, my interpretation of the idea behind it is that it balances out the standard (or average) city resistance of 25. Against a level 1 spy, mission durations are quicker than the base duration if the city resistance is below average (assuming no other modifiers apply).
There needs to be a modifier based on mission type. A gold steal taking 20 turns is one thing, a mission to knock down city defenses taking 20 turns is way too long.
That one already exists, the base missions duration depends on the mission type. For siphon missions it's 30, for the city defense mission it's 15. See the table in the OP of this thread. I'll clarify it in the proposal.
I think its a mistake to make city strength a part of the modifier.
The idea is to have some positive modifier that's always applied, preventing small and newly founded cities from always having a falling security level. Players who haven't reached Banking yet when the first player is in Renaissance also shouldn't be punished too hard.
Proposal amended: Changes to buildings removed. I also decided to follow @Stalker0 's suggestion to change Spy Power to 0%, -25%, -50%. Proposal rewritten to make it easier to understand. Previous Missions Modifier removed, this modifier was quite weak, added unnecessary complexity, and was detrimental to the intention of increasing the value of constabularies and counterspies. Those should be used to protect against constant spying in the same city.

Also this proposal failed to address the Siamese UB and the English UNW.
Both are now mentioned in the proposal. (It's Englands UA that affects Spy Resistance, not the UNW.)
Proposal sponsored by axatin.
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