Diplomacy

This is reasonably straightforward. To start with, you have to meet the other players, so again we see the importance of exploration. But then sometimes they will find you. Your relationship with another player can stand at a number of levels:

• Allies – You have to first be Declared Friends before you can become allies. Allies cannot Declare War on each other or Denounce each other. Any deals you make will likely be very favorable.
• Declared Friends – This will often happen because the AI player will suggest it. Similar to Allies, and can be upgraded to Allies quite easily.
• Friendly – You have done some things to make the other leader like you. You can probably get some good deals with them. You have a chance to become Declared Friends.
• Neutral – No bonuses or penalties.
• Unfriendly – You have done something the other leader does not like. Deals will not be favorable if you can get them.
• Denounced – If you get any deals with them they will be very unfavorable.
• At War – Until you make peace you will be accruing warmongering and war weariness penalties.

To get along better with the other leaders there are some thing you can do. Sending them a Delegation or opening an Embassy will improve relations, as will sending them a Trade Route. Gifts are also good for this, including Gold if you have a strong treasury. Keeping a promise also helps. Of course you can make it worse if you go to war and occupy a city of theirs. Breaking a promise is also bad, and being caught spying on them will make them angry. And if you are headed to Victory they become more negative towards you.

Other factors are the type of government, as leaders tend to like other leaders with the same government. And each leader has an Agenda that affects who they will like. For example, Amanitore of Nubia has an Agenda of maximizing the number of Districts in each city. So she will like other leaders who do the same, and dislike other leaders who do not. And Leaders will often give you hints about their Agenda and how well you are doing. They will pop-up to make a statement which can be either positive or negative and that tells you how they view you in terms of their Agenda.

If you go to the upper left side of the screen you will see a brief synopsis of your relationship with every other player, but you can click to open this for more information and to make deals and conduct diplomacy with each player. As soon as you meet another player, they will appear here.Usually you start out Neutral because you just met, and for Neutral there is no icon. But get to Friendly and you will see a small green smiley, then for Declared Friends a larger teal smiley, and for Allies a blue flag. For Unfriendly a sad yellow smiley, for Denounced a red sad smiley, and for At War crossed swords.

Diplomatic Visibility and Gossip

As you develop relations with another leader you earn Diplomatic Visibility that gives you some information about what they are doing. The levels of visibility you get range from None to Top Secret. The interesting thing is that this is independent of your Diplomatic Relationship to some degree. Of course being Allied with another player will give you access to a lot more information about them and their actions. You can see what level of Diplomatic Visibility you have with another leader by opening their Diplomacy screen and looking at Access Level. To go along with this is Gossip, which improves with each level of Diplomatic Visibility. You will see the gossip in the form of messages such as “Traders report that..” which is what you get early in the game. Later it may be other people doing the reporting. So both Diplomatic Visibility and Gossip are useful, and you might want to improve them. And since they are linked you improve both with any positive action. These include sending a Trade Route, sending a Delegation or Embassy, sending in a Spy on a Listening Post mission, and forming an Alliance. Later you can research Printing and gain one level with every player

Espionage

Once you reach the Renaissance Era the ablity to do espionage becomes available. In this era you can research the civic Diplomatic Service and that lets you produce your first spy, and other Civics and Technologies will increase the number you can have, up to a maximum of 6 (Note that Catherine de Medici and Wu Zetian can have one additional spy, up to 7). You produce spies like you do other units, but you don’t move them around the map. Instead, like Traders, you send them to a selected city. That can either be another player’s city (as long as you are not allied with them) or to one of your own cities. Spies sent to another player’s cities can adopt offensive missions, while ones in your own cities are defensive. And that is how Spies get killed. In any city, if there is a defensive spy stationed there and another player sends in one of their spies for a mission there is a chance that the spy will be caught and killed. When that happens you can always replace the spy by producing another one, but that takes time, uses resources, and will take more time to send the spy back in. This is because spies do not arrive instantaneously where you send them. They can take variable amounts of time.

You can send a spy to any city you have revealed, and again this has similarities to how you send Traders. When you have a Spy to send a screen will open showing you the various cities you can send it, how long it will take, what districts each city has, and what operations a spy can undertake. These are never guaranteed, of course, and a spy has two different probabilities to be concerned with. The first is the probability of succeeding in their mission, and the second is the probability of being caught or captured. Here are the missions you can assign to a spy:

• Gain Sources – The spy goes to the City Center with this mission, and it is always 100% successful and risk-free. For 24 turns spies in this city operate at two levels higher. This will increase the odds of success, but won’t affect the result. To do this, you need to use 2 spies, one in the city center to Gain Sources, the other in a district doing a mission there. Or even three spies if you have missions in multiple Districts of one city. You can have multiple spies in one city, but they can never have the same mission.
• Listening Post – The spy is sent to the City Center. Increases Diplomatic Visibility with this player for the duration of the mission. 100% successful and risk-free.
• Siphon Funds – The spy is sent to a Commercial Hub, and if successful will steal all of the Gold income of this District for the duration of the mission. You should send a spy to do this to a Commerical Hub that is fully built up and generating lots of Gold.
• Great Work Heist – The spy is sent to a Theater Square to steal a Great Work. But note that you have to steal them in the order they are presented to you, which will always be Great Works of Writing first, Great Works of Art and Artifacts second, and Great Works of Music last. If you are just trying to get as many Great Works as possible, no problem. But if you want to get a specific one, you are better off trying to trade for it.
• Sabotage Production – The spy is sent to the Industrial Zone and if successful will pillage all of the buildings in the District, but not the District itself. The other player either takes a lot longer to produce things, or has to stop other production for some number of turns while it repairs the buildings.
• Steal Tech Boost – The spy is sent to the Campus District and if successful will bring back the Eureka for a technology you don’t have yet.
• Recruit Partisans – The spy is sent to a Neighborhood District, and if successful will cause 2-4 rebel anti-cavalry units to spawn which in effect is like Barbarians suddenly showing up in the middle of his Empire. Then it will pillage the Neighborhood District.
• Disrupt Rocketry – The spy is sent to the Spaceport and pillages the District. Any Space Projects in process have to stop until the Spaceport is repaired. This is used to slow down someone who is getting close to a Science victory.
• Foment Unrest – The spy is sent to the City Center and if successful will reduce the city’s Loyalty.
• Neutralize Governor – The spy is sent to the City Center and if successful will incapacitate the Governor for a period.
• Fabricate Scandal – The spy is sent to a City-State to spread rumors and turn public opinion against another player, the result being that some number of their Envoys (at least 3) are removed.
• Breach Dam – The spy is sent to the Dam District and if successful pillages the Dam causing a Flood, and leaving the city vulnerable to flooding until the Dam is repaiSpies can gain experiencred

Spies can gain experience from their activites, leading to Promotions that move them up to higher levels. The levels are Recruit, Agent, Secret Agent, and Master Spy. The Promotion system is very similar to the one for Military units, and there are many you can choose from. But once you have made your choice you are stuck with it, so choose wisely. In many of the missions above the effect of the mission will depend on the level of the Spy involved.

Capture and Escape

Sometimes your spy is discovered while attempting your mission. This can happen even if the mission was successful, e.g. they successfully sabotage production but are discovered. They first have a chance to escape, and if successful they show up back in your Capital and can receive a new mission. If they are discovered in a city with an Aerodrome they can attempt to escape by air, which only takes one turn, but thas the lowest chance of success. If it is a city with a Harbor they can try by boat, which takes two turns but is slightly more likely to succeed. If in a city with a Commercial Hub they can try by vehicle, which takes three turns but has even better odds. Finally, you can always choose by foot, which takes four turns but has the best odds of all. If they are caught while trying to escape, they are held as a captive by the other player, but you can usually make a trade of some kind to get them back. But while they are captives they still count towards your limit on how many spies you can have.