So, a summary of the AI in the last patch. I decided to play a game as Australia on King level, because I haven't played since launch week and wanted to have an easy game seeing how it all worked again. Normally I play on Emperor in previous civ games, and Immortal if I want a real challenge. King is easy mode - the AI will launch attacks and try to compete, and get minor bonuses, but in the long run I'll win.
Start off very isolated, with tons of pastures near by which look to generate ridiculous bonuses. Later on I discover they are useless, as you can't build Outback Stations on hills, but that's neither here or there. I slowly expand to the west, as it's the only direction I can go in. After going through a lot of hills, jungle and past a mountain range, I encounter my nearest neighbors - Arabia, and Brazil. Above them is France, and that leaves the 4 of us on this continent. I'm on an isolated spur on the eastern side, and there's vast amounts of room between me and any competition. None are expanding in any way in my direction, and I only make one extra city but build a decent military force as a precaution.
Turn 80, out of the blue, both Arabia and Brazil declare war on me. They aren't friends with each other, neither denounced me, and obviously at this stage I can't see their modifiers. Later on I discover neither has a hidden agenda that should cause this (in fact, Brazil's agenda should make them love me - I'm not competing for great people at all, and I'm earning tons of money). In Civ 6 it feels like there's an artificial cap on when AIs can declare war, and once you hit that turn a bunch will no matter what.
So, regardless of the fact we aren't competing in any way, there's tons of difficult terrain between us, and our agenda's don't clash, I'm now at war with 2 civs at once. Why they didn't declare on each OTHER is beyond me - they are literally next to each other and already competing over territory. I marshal my army of archers, add in a couple of pike man, and slowly trek towards their cities. Arabia is closer than Brazil, so I target them first.
When I get there, much to my surprise - they don't actually have an army. They have a few units, but they don't even look like they were planning on attacking me. Why declare war if you aren't going to attack?
Nevertheless, I quickly take a smaller outer city, then start seiging his capital. Note that this takes a lot of turns - I'm going slow and playing cautiously, the terrain is awful, etc. Arabia still doesn't actually build many units - he pulls out a few chariots and sends them towards me. Problem is, I get to shoot at them once before they hit, and once that happens the AI clearly breaks - they just start swapping positions on the map in front of my army, which of course means I just ping them to death and then take the capital. I then take brazil's nearest city, then call it a day. Brazil literally had no units other than a single warrior I ran into. Obviously at this stage the rest of the known world loathes and despises me for being a war monger, despite the fact I didn't eradicate any civ and was the victim of the declaration of war.
Over the course of the game I then slowly expand, settling the weirdly empty vast continent to the east, and meeting the games other civs - Kongo, Sumeria, Greece (gorgo) and Germany. At around turn 150, out of the blue, India and Sumeria declare war on me. Now, they are friends so this sort of makes sense - but they are both on another continent, we aren't competing in any sense,. So the actual declaration is just weird. Especially as there are other civs far closer to them. Neither actually HAS an army or navy to speak of, so using just a caravel and a frigate I conquer one of Sumeria's cities.
Suddenly, out of now-where, France declares an attack! Now, this is partly surprising because France was the only civ in the game who didnt dislike me. We were neutral because we had trading routes, I was strong in espionage, and generally we'd left each other alone as she was at war with Brazil (who still hated me). FRance had a small colony near my main secondary outpost, where I had two cities that were woefully under-defended - one crossbowman in each city, no encampments or city walls, both on the coast so vulnerable to naval attack. Whilst I was annoyed at the randomness of the DoW, I was pleased the AI had caught me in a vulnerable spot, and identified where it should strike. They had a large fleet of crossbow men, pikeman and knights that all landed on my shores - for once the AI was going to war with an actual army! A challenge!
Only not. They didn't once attack my cities. Instead, they marched up and down around them, being whittled down by my archer fire as I rapidly build up a huge archer force and then promptly killed them all. I also realized that they had zero naval ships - so had I had any of my fleet in that area, their entire army would have been sunk instantly. So despite having two very vulnerable locations, attacking by surprise with a massive, tech appropriate army, they accomplished nothing other than the deaths of thousands of poor French knights and peasants. At that point, I ended the game.
Ultimately, the AI doesn't work, at all. Quick summary:
1) It's even more aggressive in declaring war than Civ 5, and never seems to forgive or forget war monger penalties. Unlike Civ 5 however, it often doesn't actually build armies when it declares war.
2) The declarations have no basis in any form of strategy - I was targeted not because I was winning (I wasn't, at one point Kongo was two eras ahead of me), not because I was weak, and not because we were competiting over resources - it just seemed to happen. Only one of the 5 DoW actually had a sound reason for occurring, when France tried to pick off my isolated, vulnerable colonies.
3) If the AI does have units, it doesn't know how to use them at all. Again, far worse than even vanilla civ 5. It seems there's something wrong with what happens when its units are damaged - it starts just swapping them back and forth, no matter what else is nearby. Numerous times I'd watch as their forces just paraded up and down in front of my cities and ranged troops to slowly be killed.
4) The AI doesn't understand districts. It seems to just build to fill out it's district spots, so by the time industrial districts appear it can't build any. There were literally *zero* industrial districts in the entire game at this point.
5) It doesn't provide escorts, *still*. I stole workers and settlers with abandon. Also, when France launched it's naval attack, they didn't have a single ship to shield their army as is approached. Plus, my cities were on the coast so extremely vulnerable to naval conquest.
Ultimately, the game remains in a completely broken state. I'm not the best civ player by any stretch, but there simply isn't any challenge here. The AI cannot compete at all, and doesn't act in any way rationally - random declarations of war are bad enough, but when the enemy has no army to actually fight? It doesn't understand basic systems at all either - it neglects proper districts, formations and trade significantly. I've been playing Civ since Civ 1 first came out, and I've never before been so aware of how utterly, completely, the AI is failing at the game. Watching their armies parade back and forth in front of archers who are slowly killing them is just dumb.