I would like to choose high intelligence A.I but with no economy or unit buffs like you could in GC2.I hate buffed A.I but I do not want the A.I to be less effective on purpose as it stands on normal setting in the game.
Choose normal for the world difficulty and Challenging for the opponent difficulty. That is what you want and there are no bonuses to you or AI.
I see no tool tip in opponent difficulty so I presume it would get the same economy and unit buffs as world level.
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