General Advices - If you only want counterplay advice for CV skip below: As Zdarg pointed out, 350 - 425 turns is too much, rather than failing to prevent them from winning, you fail to win fast. As such it's hard to give specific advices since winning fast enough covers a lot and is based on what victory you're going for. For example, If you're going for Science Victory, the specific advices would be to spam cities, build Campus first, run Natural Philosophy and Rationalism cards, aim for wonders like Great Library and Oxford University. It's possible even these recommendations are not optimal so you would have to wait for someone who is actually decent at the game, which I am not, to give you something better. However, I play Settler quite a lot when I want to mess around with stuff, so in my noobness I do feel like I can ironically give some advices for start. You will likely develop your own way different from mine, though, and it's highly likely none of this works beyond that difficulty, so some might probably argue it is best to not get bad customs that won't work. On Settler If you don't go for Religion I would recommend making one tall city 10+ population. In that city get Pingala (the Governor) with all Promotions, Apadana (requires it to be Capital City, but If you can't make this all in there all you'll lose is Envoy dominance which isn't too bad), Kilwa Kisiwani (once again, If you have no coast not too bad to lose this), Oxford University, Broadway and Oracle. Anywhere else (If you can, still go for Capital) aim for Big Ben, Potala Palace and Forbidden City, though missing one of these won't be bad, it just makes things easier. Likewise, Casa de Contractión makes things faster even If you don't use 80% of its benefits, the 3 Governor Titles are good on their own. The Potala Ben City tio give you +1 Economic, Diplomatic and Wildcard cards, which gives you huge bonuses. It doesn't matter in what city they are. Same for Casa. The others though are best stacked in one city with Pingala that grows high. Pingala will give you +1 Science and Culture per Pop, Apadana gives 2 Envoys for each Wonder built (build Oracle first, then Apadana for maximal effect, though AI doesn't focus on Oracle so you may pull out Apadana and then Oracle to cover each Wonder with 2 Envoys), this gives you dominance over City-States, If you are Souzerain of City-States, Kilwa gives great benefits to its city. Kilwa's tooltip is confusing but it should allegedly work this way: If you are Souzerain of Scientific City-State this city gets +15% Science. If you are Souzerain of 2 or more Scientific City-States, each city gets +15% Science and this city gets additional +15% Science to what it already had. Combine Pingala (+15%), Broadway/Oxford (+20%), Kilwa with Souzeracy over 2 Scientific and Cultural City-States (+30%) and you may achieve something like 65% Science and Culture boost in the city. That alone gives you dominance of Technologies and Civics. With steps written below (the cards, plus Apadana plus Kilwa), you will also have diplomatic dominance. As such, you will mostly dictate the game, barring Religion and should be able to experiment with anything and win fast enough. As for Government, go Classical Rep -> Merchant Rep -> Communism, as for cards, God King until you get Pnatheon, then Urban Planning until you get Corveé (for wonders), maintain Corveé. At first Government go for Increased Influence. If you haven't met any City State by that point, go for +1 Envoy at first Envoy into Increased Influence when you met at least half or more CSs. Go for Natural Philosophy, Rationalism, Aesthetics, Merchant Confederation when it comes to other cards. Harbor big amount of Gold and keep trying buying Great Works from others with generous offers. If they can accept offer, try lowering the Gold you give them to find the lowest they go. If you have useless tile adjacent to River, use it for Hermitage and then Orságh. Once again, these advices are general paths to dominate Settler difficulty for testing stuff and winning fast enough. In higher difficulty, you can't focus so all over the place I suppose and you must wait for someone better to give better advice. Counterplay: So If all you want to know is how to practically prevent someone from winning CV - large amounts of Culture, taking Tourism If you can and winning fast enough. Spies don't do as much against CV unless you have good empowermnets and trust their stealing. Culture Victory, when simplified, works like this (or at least I assume so): Each civ accumulates Lifetime Culture. Each civ accumulates Lifetime Tourism towards each other. This is mostly the same number except for specific modifiers like +25% Tourism towards civ you have Trade Route to etc. In order to win, your Lifetime Tourism must be higher than Lifetime Culture of each civ. Let's imagine a game where Poland has all the time from the start 10 Culture per Turn. From Turn 10 onwards, you keep at all times 20 Tourism per Turn towards them. At Turn 10 Poland = 100 Culture; You = 0 Tourism. At Turn 15 Poland = 150 Culture; You = 100 Tourism. At Turn 20 Poland = 200 Culture; You = 200 Tourism. At Turn 21 Poland = 210 Culture; You = 220 Tourism. Do this with all other civs and you won. To prevent that most reliably you must simply keep your Culture high. Less reliably, you must try to buy their Great Works which lowers their Tourism. They may try to ibvade you with Rock Bands. There's a card which gives you - Amenities but prevent them from entering your civ. From that point on it's just about winning sooner than they do. EDIT: After all this is written though, I realized neither of us asked what Game Speed you're playing on, maybe it's not that late in the game relative to that?