I know that the AI is still a work in progress but I felt compelled to outline my past experience.

I played on a tiny map against 3 AI opponents at the difficulties Hard, Extreme and Ridiculous. Right now as far as I can see, the only thing that the difficulty changes is what sort of bonuses the AI receives. Such blatant cheating is a real turn-off when it comes to strategy games (especially when a city starts out 9999 of all stats). Unfortunately even with their amazing advantages, the AI was still a complete pushover.

For the entire game, not one AI opponent constructed more than one (founding) city. And in previous games where the AI has founded more than one city, they have neglected them, failing to construct the necessary housing to get them past level 1. Cities also seem to be founded in rather poor locations, failing to take advantage of available bonuses on the map.

With huge bonuses to finances, research (both magical and technological) and prestige it was extremely unsatisfying seeing that the AI was building squads of pioneers. The most powerful AI had an army, consisting of appox 33 pioneers, and one footman. As pathetic as this army was, what was even more disturbing was the fact that when war broke out between our two civilizations the AI left this army behind and attacked me exclusively with their sovereign! Naturally I slaughtered this single LVL 1 sovereign. Not only did I slaughter the AI sovereign, but the enemy sovereign didn't cast a single spell during the tactical battle despite having 25 mana at her disposal.

So just to recap the current issues with the AI:

• AI resorts to massive cheating to gain an advantage over the player
• AI fails to expand properly by founding new cities and supporting them
• AI fails to take advantage of map resources when placing their cities
• AI does not use their army when attacking, they'll come right at you with just their sovereign
• AI does not use available resources to build an appropriate army
• AI does not explore the map: their sovereign will be at LVL 1, 100 turns into a game
• AI does not make use of spell casting during combat