Steal research: This should not be a whole advance, but more in the mould of Imperialism II, where spies speed up your research on subjects your opponants have researched.

Poison water supply: This needs expanding. Biological agents such as cholera for example, as well as some chemicals. Could have a production effect rather than a population decrease.

Cyber Attack: Steal money from city's banks, delay production, decrease trade. Any of these are possible.

Note that I think these actions should be given different names when used in different eras. eg the "Cyber Attack" above would be called something like "Raid gold reserves"

And also,

quote: Steal research: This should not be a whole advance, but more in the mould of Imperialism II, where spies speed up your research on subjects your opponants have researched.

I think maybe the best thing is to let the Diplomat act as the first wave of a large army. If you are quite powerful and at war with that civilization, the Diplomat should be able to offer the city a chance to surrender without bloodshed. That has been done numerous times throughout history, and it gives the city a chance to reject.

As for any new changes, I think we will have to wait and see what comes out of developments in other areas. For example, the spy should be able to destroy the Harbor which should disrupt the city's participation in the market system. I don't mean that there should be a special function for that, I just mean if it is a destroyed improvement, that should be the result.

Another is that spies should be able to cause revolutions not from one civilization to another but to upset the government of the enemy. A spy sneaks in and dumps a lot of rhetoric into the city, and the people demand a different form of government. It ties into whether there are actual revolutions that come from the people rather than the player, so we'll have to see about that.

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"...The highest realization of warfare is to attack the enemy's plans; next is to attack their alliances; next to attack their army; and the lowest is to attack their fortified cities." - Sun Tzu

quote: Another is that spies should be able to cause revolutions not from one civilization to another but to upset the government of the enemy. A spy sneaks in and dumps a lot of rhetoric into the city, and the people demand a different form of government

This is a good idea, but it is already indirect in the game because spies can make cities unhappy - and in a democracy this could lead to anarchy.

Also what I was saying ties into my theory that popular revolts should spread from city to city and that government troops are required to reestablish government control in revolting cities. Such an ability for a spy to do this would be incredibly useful for distracting enemy troops.

I posted a message in the thread on Revolutions that explained it more in depth.

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"...The highest realization of warfare is to attack the enemy's plans; next is to attack their alliances; next to attack their army; and the lowest is to attack their fortified cities." - Sun Tzu

quote: As for any new changes, I think we will have to wait and see what comes out of developments in other areas. For example, the spy should be able to destroy the Harbor which should disrupt the city's participation in the market system. I don't mean that there should be a special function for that, I just mean if it is a destroyed improvement, that should be the result.

Good idea. I think cities should have thier own system to decide that. Some cities could on thier own, be less loving of your govt. for whatever reasons and therefore have a very low price - inviting peacefull buying off.

I also think some cities can use the war momentum to declare their independance or to join the other side. Completely on thier own.

quote: Another is that spies should be able to cause revolutions not from one civilization to another but to upset the government of the enemy. A spy sneaks in and dumps a lot of rhetoric into the city, and the people demand a different form of government. It ties into whether there are actual revolutions that come from the people rather than the player, so we'll have to see about that.

very good ideas.