OP, you can see a list of AI bonuses by difficulty in this folder: CBO/Balances Changes/Difficulty
You have to decipher some coding, but I'm sure some folks here could help you with that if need be.
I think they start with more and more experienced units. So one thing you can forget about is befriending CS by helping them against barbarians. Another one is delaying the army. But I'm still strugling with King, just talking by hearsay.
True regarding barbarian encampments, but certainly not regarding barbarian invasions in city-states. The key is being nearby - don't move your units across the map in hopes of farming influence from an invasion, because if an AI has units nearby they WILL move in before you do.
It's gusto if the city-state is nearby.
I typically play immortal because I feel like it gives me more options but I have played and won on diety. Obviously things are going to change based on your civ/map but in general I've found the following:
- Delay shrine/pantheon/religion unless you have a religious civ or a possibility for a great pantheon that will guarantee a religion. Even with a great pantheon it can be tough to get a religion because the AI can have more workers to improve tiles faster and get more faith buildings online faster and ally religious city states more easily.
- The AI doesn't have that much larger armies than immortal.
- I cannot keep up with the AI in terms of science, culture and military while playing peaceful.
- The only way I can win is by completely wiping out my weaker neighbors and then expanding pretty wide. The only advantage that I have over the AI is in maneuvering units so I play to that strength.
I'm not sure if other people have success on diety playing peacefully but I generally cannot unless I have a great starting location.
Disagree on religion. If you want one you can get one in
any game.
Should get a shrine: after the initial scout in capital; first or second in satellites, depending on your production (build a monument first if high production, since it won't delay the faith too much). Get settlers out ASAP to make it happen. Then pick a pantheon that guarantees faith generation quickly (God of All Creation, faith on marsh/lake/oasis, faith per X citizens & council, you get the point). Tradition is very useful for +2 faith, though not necessary.
Stonehenge is cheated for religion; the AI doesn't prioritize it at all, so if your capital has reasonable production -tradition and the production + engineer slot help there- and you go for it early its almost guaranteed. +3 faith & lump faith really get you going.
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Agree on expansion; it's nigh impossible to win tall imo, the AI will always catch up because of its bonuses. For passive play you need to go wide (wider than the AIs anyway).
Before walls and mathematics, 3-4 archers and 1-2 warriors/spearmen can go very far, aka take any city not protected by rough terrain - your archers ought to stay at range two while shooting. Gotta play slow and deliberate, let their units come to you instead of being offensive and never sacrifice one of your units for theirs, because their numbers will eventually swallow you otherwise.