I would like to know the answer to this since I tried contacting support to ask them to explain this but did not get a straightforward answer.
What is considered when playing against it such as level, hidden match-making rating, the art of war medals etc? Does this like affect the way that they become more challenging based on stats? Since some time you feel after 2 mastery that the third time you play against it is different hardest A.I
Like I have been noticing some change patterns regarding the match previously I used the same civ two times same map on the first match the A. I sent all his villagers to die in my town centre while trying to build behind it then when I denied his gold just stood there 8 min without gathering any resources this was against intermediate or building double walls where they do stone walls and then inside the stone wall wooden wall as well.
I have also noticed that Easy A.I have started to play differently from all the games I played that did not build Blacksmith if it did never took upgrades from there it has started to do that as well. Sometimes they age up even in 3-4min time some cases they just play Stardew Valley age up within 15-30 min to age two. Sometimes they play super aggressively in early games from easy to hardest.