Not sure if anyone has posted this before, but I may as well give my version of it. Works nearly every time on Immortal, Deity requires a little more luck. Civ: Mayans - by far the best for ICS. Start: Settle on hill for early production. Ideally settle on mining luxury with one more lux in immediate radius. Initial Build: Scout, Scout (or Atlatlist if will complete before Pottery), Pyramid, Monument, Settler. Worker can be purchased from gold gathered by meeting city states and selling embassies to AI (or if settled on lux then from the lux). Initial Research: Pottery, lux techs, The Wheel, Trapping, Construction (hold off for as long as you can if you don't need the happiness) -> Theology For those that don't know, the general idea of ICS is to build a very large number of cities as tightly packed as possible. Aside from the capital, the quality of terrain and resources settled on/near doesn't matter. It is about maximising the number of cities in a given area, which requires a fair amount of foresight (making sure that projected city locations are at least three tiles from city states and not on mountains etc.). ICS empires should never stop expanding. The obvious challenge is managing happiness. There are several critical beliefs and policies required for maximum potential to be achieved: Policies: Meritocracy: +1 happiness for every connected city (and the -5% for population) Order opener: +1 happiness per city Protectionism: +2 happiness per lux Beliefs: +1 happiness for every following city +1 happiness from shrines for cities with 3 followers (perfect synergy with Pyramids) Pagodas etc. are too costly to benefit a very wide empire. Per-city boosts are much more effective. [EDIT: ignore this! I have now been made to see their use!] Because the two listed beliefs are popular with the AI, it is very important to found a religion quickly. Therefore each new city's first build should be a Pyramid (though I would recommend purchasing in the 2nd and 3rd cities). If playing Immortal, religions are founded slightly later so I always pick Messenger of Gods for my Pantheon (+2 Science for cities with trade route). Combined with the Pyramid, this gives +4 science per city, which builds up massively. However, unless a faith-giving natural wonder is nearby in a Deity game, I would suggest picking whichever Pantheon yields the most faith, since getting the happiness from religion is more important than the +2 science. Build order in each city (not capital): Pyramid, Monument, (Circus), Colosseum, Market/Library (order depends on whether you need gold or science), Granary, Workshop After three cities have been settled, get capital to 5 pop and start mashing out the settlers and atlatlists/composite bowmen for defence. Get religion up, use great prophet from Long Count to enhance (getting shrine belief listed above and religious texts for 34% spreading speed). Do quests for religious city states to get to the initial 200 faith and then focus on mercantile. If you're happy, then you're not building enough cities! The Piety opener for half Pyramid cost isn't usually worth it - you already need 6 from Liberty, 4 from Commerce and the Order opener. Given the huge increase in policy costs you'll be causing, each one counts for a lot. Avoid growth and put to production focus when you get 3 pop per city. If you get the +2 production if city has a specialist belief (which you should), then after the workshop, let each city get to 4 pop and assign a production specialist - that's +4.4 production for one extra pop. In order to combat AI invasions, advance your cities in lines perpendicular to the movement of their troops - that way, their units will be trapped in the firing range of at least two cities and garrisoned bowmen. If you go on a conquering spree, raze any cities you capture. Build your own cities there later. You need to be able to control every aspect of your cities and not have flabby puppets draining your happiness (or annexed cities consuming 4gpt from a courthouse). Once the happiness is rolling in, feel free to grow a few of your better cities (for production purposes that is) so that more units can be pushed to the very large front line. Big Ben is probably the only wonder worth building, and possibly Forbidden Palace. You're going to need to purchase units rather than build a lot of the time. If I've missed anything (which I probably have!), please post! Happy sprawling!