2K are a crafty lot.

Last time I spoke with them, they swore black and blue that 2K Marin (BioShock, BioShock 2) had absolutely nothing to do with the 2K-owned studio Firaxis. No collaboration, no association, and no chance that they'd pass on my request to Mr Meier to make a follow-up to his excellent 2006 Railroads title. The ever-so-subtle head tilt and look of sympathy was clearly duplicitous, and suspiciously well practised, although fans of the Railroads series will be well accustomed to pity.

I say this because the interface in Civilization V is pure Rapture. Art Deco. It's clean, stylish, and apart from the notable distinction of being above water, could easily have been designed by Andrew Ryan. If there isn't any mutual collaboration in progress, then it's time for 2K Marin to change their locks and hammer large pieces of crooked wood against their windows.

This, however, is certainly no cause for complaint. Virtually everything about Civilization V is refined in a similar way, from the unit animations to the sound effects, from the larger-than-life cast of characters to the studiously detailed terrain placement, the title is an exemplification of lessons learned over nearly two decades of strategy game design.

It would be unfair to claim that Civilization V is an outright amalgamation of Civilization IV and Civilization Revolution. The DNA is obvious, however many gameplay elements are clearly incorporated to extend the complexity of the gameplay, rather than simplify it, as was the case with Revolution. The most noticeable difference is that the terrain is now pegged out in hexagonal polygons, rather than the traditional squares, which facilitates your movement without the need to question which tiles are wholly associated with either land or water.

Along with the increased logic afforded to your unit pathing, this move to a hexagonal structure allows the terrain to take on a more natural contour, and the associated opportunity to increase environmental detail has not been lost on Firaxis. No matter the level of zoom, the world is a finely detailed entity, with subtle DirectX 11 lighting effects and clever placement of game assets complimenting your march through the ages.

It's a deceptive facade. Underneath the new hex layout and the fancy graphics beats the heart of a ground-up remake. Firaxis, with the sweep of a pen, have managed to achieve what the real world has singularly failed to do - namely the abolition of religion. Temples simply add happiness and culture. Gone too, any form of espionage. You can't even rename your cities. Indeed, it may appear from the outset that most of the changes introduced with the massive overhaul that was Civilization IV have been removed, or at least modified in a substantial way.

Most of the control of your civilization has been handed over to a new "Social Policy" interface, which replaces the firm rule of a particular government style with variants based on ideals of your own choosing. You can adopt five various policies within eight categories, the majority of which alter your efficiency in producing the staple requirements of all powerful nations - gold, science, culture, and the acquisition of troops. It's a branched system with prerequisites, so choose wisely - some will compliment your growth if you're overly militaristic, some will hamstring you if you're more interested in science.

Possibly the most dramatic move away from established Civ canon is the requirement now for each unit to occupy its own tile independently of any other unit. Gone are the days of stacking hordes of riflemen on top of a cliff - you'll now need to play a much more strategic game of supply and demand to ensure you have armies constantly willing to replace those headed to the front line.

This may sound like a chore, but to balance out any defensive weakness introduced by this radical combat alteration, cities are imbued with their own native attack abilities. Even without a sentried unit within your city, it's capable of repelling loosely organised mobs of barbarians, but not much else. Ranged units behind city walls can slaughter determined attacks from a considerable distance, preventing (in the early stages of the game, at least) being run over by your inability to field stacks of defensive units.

Combat itself still largely follows the same methods used from time immemorial. You'll be given odds on success prior to any engagement, at which point you can either choose to continue with your warmongering, or perhaps retreat to a safe place in which to start the diplomatic process instead. The act of ingratiation with your neighbours is again indicative of the attention to detail lavished on this latest instalment - the AI leaders are compelling, humorous, and narrated expertly. It could be argued that the lack of religion has removed some of the arbitrary outcomes that often occur in Civilization IV diplomacy, too.

Aside from enemy combatants, you'll also come across barbarian camps, the destruction of which will provide a relatively easy flow of gold at the early stages of the game. Assisting here are the new "city states", which act as mini-civilizations in their own right. Occupying a typically small corner of the map, they'll frequently offer missions in exchange for gold and benefits, such as being able to move your troops unhindered across their territory. The amount of effort you contribute towards either assisting them, or destroying them, can make a substantial difference to your eventual strength, however if it's all a bit too cerebral the casual player can switch them off.

It's clear that the developmental focus here has been the refinement of many key concepts that were otherwise redundant or poorly integrated with previous Civ installments. The lack of unit stacking and the hexagonal tile layout has introduced a level of strategy not unlike a massive game of chess, whereby the player is now required to ascertain in advance not only the production required to front an army, but the strategic positioning of each and every unit at any given time.

The removal of religion and the introduction of a variable social policy has ensured that no two combatants will every be entirely matched, which more closely reproduces real world politics and serves to add a touch of chaos to the mixture. Similarly, the hugely improved diplomatic mechanism, with wildly different outcomes possible, again ensure that no two games will ever be quite the same. If there's one aspect to be wary of, it's that the combat is seemingly weighted towards ranged units - as our preview code lacked the capacity to set up a multiplayer match against a human foe, it's too soon to see if a rush game consisting of high production and swarms of ranged units could introduce a game breaking scenario.

Our preview code also lacked large maps and the ability to mod anything, so we've begun the long wait until the game releases on September 24 before passing further judgement. From what we've seen so far however, it adheres to the "one more turn" concept so central to each Civilization release, so be prepared to sacrifice a good deal of your life on this one.