Spy Games

Spies are real units.

Spies get a limited number of “operations” which they can use to either detect other spies, or perform missions in foreign territory. (This is similar to builder “charges”, but spies with zero operations remain on the map)

Spy “operations” automatically regenerate once every 5 turns or they can be purchased with gold. France gets a discount when purchasing operations with gold.

Spies are invisible to all units, including other spies, except if:

-Spies use their “detect spy” action. The more “operations” used for this, the further away other spies will be detected. (1 operation for 2 tile radius, 2 operations for 3 tile radius)

-Friendly cities, encampments, or spies can pay a fee to “detect spy” for one turn (30 gold for 1 tile radius, 90 gold for 2 tile radius, 180 gold for 3 tile radius, or city project).

If a spy is “detected” they will be alerted and tracked for 5 turns.

Spies that have been “detected” cannot take part in missions until they go undercover again.

A spy can only be caught by another spy that ends its turn on the same tile. Note: this can happen even if the enemy spy hasn’t been “detected”.

Military units cannot capture an enemy spy, but they can block their movement once detected.

A spy’s nationality will remain secret until caught.

An enemy spy caught in friendly territory is caught red-handed
An enemy spy detected in friendly territory but captured in neutral territory is caught red-handed
An enemy spy that makes it back to it’s own territory has escaped.
If your own spy moves into enemy territory they now become in danger of being captured.

Spies that meet in neutral territory will reveal each other’s nationality and automatically track each other’s location for 5 turns.

Beware that your spy’s location can be sold to other nations on the trade screen.

If your spy is just passing through a friendly nation’s territory and you don’t intend to use them offensively, you can “declare” your spy’s location to your friend for 5 turns.

Spies can use enemy airports and seaports for movement as if they were their own.


Missions

Missions that are performed in foreign districts can be Passive, Active or Sabotage.

Active and sabotage missions cost an “operation” to initiate, but only take 1 turn to execute.

Active and sabotage missions have 4 possible outcomes: Successful undetected, unsuccessful undetected, successful detected, unsuccessful detected

City Center Passive: Increase diplomatic visibility
City Center Active: Show the location of the nearest enemy spy
City Center Sabotage: Damage city HP to ½

Encampment Passive: Notify when military unit is being produced by that city and number of turns to complete
Encampment Active: See location of all land units for one turn.
Encampment Sabotage: Damage encampment HP to ½

Industrial Passive: Notify when a building is being produced by that city and number of turns to complete
Industrial Active: Steal random great person points
Industrial Sabotage: Reset production of the current city build order to ½ way done

Campus Passive: Notify when a new technology is being researched and number of turns to complete
Campus Active: Steal a eureka bonus.
Campus Sabotage: Reset research of the current tech to ½ way done

Commerce Passive: Steal, and I mean actually steal, a very small amount of gold per turn.
Commerce Active: See location of all trade units for one turn.
Commerce Sabotage: Steal a large amount of gold

Holy Site Passive: Steal a very small amount of faith per turn.
Holy Site Active: Steal relic
Holy Site Sabotage: Steal a large amount of faith

Culture Site Passive: Notify when a new civic is being researched and number of turns to complete
Culture Site Active: Steal art
Culture Sabotage: Reset research of the current civic to ½ way done

Seaport Passive: Notify when naval unit is being produced and number of turns to complete
Seaport Active: See location of all military naval units for one turn.
Seaport Sabotage: Plunder trade route moving through the seaport.

Launch Complex Passive: Notify of any space race projects or nuclear weapons being built and number of turns to complete
Launch Complex Active: Unable to use “spy satellite” city project for 10 turns (see spy satellites section)
Launch Complex Sabotage: Destroy stored nuclear weapon

Neighborhood Passive: Increase the city’s war weariness
Neighborhood Active: Show the location of all enemy civilian units including religious units.
Neighborhood Sabotage: Reduce the number of citizens in the city by 1

Airport Passive: Notify of any aircraft being built and number of turns to complete
Airport Active: See location of all air units for one turn.
Airport Sabotage: Destroy a military aircraft unit at the base.

City State Passive: +1 Influence point per turn
City State Active: Generate additional city state mission for you to complete
City State Sabotage: Discredit one of the Suzerain’s Envoys

Spies can pillage any tile, but keep in mind that pillaging and sabotage make your spy’s location obvious.


Spy Promotions

Level 1:
No penalty for movement through hills
or
No penalty for movement through forests

Level 2:
Detected spies are tracked for an additional 3 turns
or
Spy “operations” refill in 4 turns instead of 5

Level 3:
“Detect spy” action only uses 1 “operation” to see a 3 tile radius
or
+2 sight (does not affect the detection of other spies)

Level 4:
+2 movement


Spy Satellites

Cities with a launch complex can build the Spy Satellite city project that would allow you to see a 4 tile radius anywhere on the map for 2 turns.

 

Yes, I've hoped the game would move this direction going back to C4 and all the discussions around the SuperSpy Mod back in the day. https://forums.civfanatics.com/threads/bts-super-spies.259221/

Implemented correctly, this would add a lot to the game in terms of strategy and fun.