[BigJMoney]

What about taking a different approach to AI? Instead of trying to make an AI "think" like a human or "seem" like a human, why not just start small?

First of all, to have the most basic aspects of diplomacy, the AI doesn't actually have to be interactable, it just needs to exhibit relations. Each AI nation chooses allies, neutrals and enemies. This can be completely random, it doesn't need to be based on relative strength and intel. If it were, the player could exploit this by focusing on large armies to keep enemies from declaring war. Neutral relations would mean they ignore you. Allies would send a message that says, "X wants to ally with you, do you accept?" They will then periodically send surplus resources to their ally, and stealthy units will never be discovered and attacked in their lands. Now, the player can't alter relations manually, but he can choose to get involved. If a nation is at war with another, he can send resources to the one he wants to see win.

A few necessities:

* war should only be declared on those adjacent
* war can be declared at any time
* if a nation is already at war, they should not choose to declare war with someone else
* neutrals should still scout and instill uprising
* spies caught instilling unrest in allied territory change relation to neutral
* assassins caught in assassinations in allied territory change the relation to enemy
* alliances can otherwise be broken at any time
* alliances and wars can be seen by all

It's not a lot, but it allows the player some ability to backstab and be backstabbed. It's also non-exploitable. The only thing the player can do is declare war. Maybe sending ally requests to neutrals have an N% chance of them saying yes. To add some risk, maybe also give it a smaller chance of triggering war.

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