Civilization V was released in 2010 and went on to be a big success story. The franchise has sold over 33 million units over the years with Civilization V being the best-selling version having sold around 8 million units sold worldwide.
And the gamer reviews for Civilization V were pretty good too. G5 gave it 5 out of 5. PC Gamer gave it 98 out of 100, and Game Informer 9.75 out of 10. And Civilization V took the 'Best Strategy Game' award at the 2011 BAFTA Games Awards.
That's not to say there weren't a few gripes with Civilization V though. One major quibble was the quality of the AI game opponents and their lack of smarts when conducting negotiations and diplomacy.
So how have Firaxis Games tried to improve on the success of Civilization V?
The latest version, Civilization VI, is due for release on October 21 2016. The same team that developed Civilization V have also worked on its successor. And it's already been named 'Best PC Game' and 'Best Strategy Game' at the Game Critics Awards.
So what's new? Well, the developers have suggested in various interviews that research found many gamers had come to find playing Civilization V one-dimensional.
The big aim with Civilization VI has been to create a game that makes gamers think on their feet a lot more. A more reactive experience is what the developers have tried to achieve.
And with that in mind they've made some big new changes for Civilization VI. For a start city development has been overhauled. Now when you've built a city center you have to specialize the function of that city. It can become a specialist military, industry or science city, say – but it can't contain elements of everything.
And that means terrain is much more important than in previous games. You have to think through and match up the function of your city with the landscape around it now for the best results. If you're building an industrial city you're going to need natural resources, for example.
That will impact on how you have to think about strategy too. There will cities that you'll need to identify as being vitally important to your opponents' infrastructure that you can attack, and cities that you'll need to place extra emphasis on defending yourself.
The AI opponents have been upgraded too. So the historical figures like Gandhi and Teddy Roosevelt that you're playing against will be more intelligent and cunning. Each has their own particular personality for you to read and monitor, but also hidden agendas that you'll have to work hard to decipher.
And unlike in previous Civilization games there are much greater rewards to be had for developing the culture of your empire. In past versions of the game you will have found it much harder to succeed with an emphasis on cultural development compared to, say, science or your military. So for the first time developing drama, philosophy and poetry could be your route to victory.