I own 100 settlements as Macedon right now, playing on Very Hard and there is no faction equal to power.
During the campaign, the Seleucids were very strong with about 10-12 settlements ant a few satrapies, then the Chorasmii took their place owning everything from bactria and all way to the west of the caspian sea, but eventualy ran out of food, and the same happened with deferent factions, Cyrenaica, nassamones, Rome etc.
My point is that when you pass the midle of the game and have become super power, with 15 armies etc, there is no other faction to confort you and become magor competitor and your prime enemy, its just a race against time to complete the objectives.
The only difficulty is to control vast areas and at the same time expand with a limited no of armies.
Im not sure wetther the AI will eventually win the game, with what i have seen it will grow strong, run out of foon and die.Its totaly incapable to manage the economy, the bildings or even to present armies with advance unit types later in the game.
Unfortunately....
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