From what I can see the other factions do engage in some form of meaningful diplomacy with each other, obviously it's not possible to really know whats going on between them though. I have seen alliances form between factions with common enemies, and it is entirely likely that they are making deals to attack the player. The AI is better across the board in this game, but it frustrates me to see that in practice the way they deal with the player doesn't seem to have changed much from Rome. I had high hopes for the diplomatic aspect of this game but thus far it hasn't lived up to those hopes. It's still a great game and ill be playing it for a long time to come regardless of if changes are made or not.
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