After a controversial launch, Empire has gone on to become one of the sleeper hits of the Total War series. A few weeks before the standalone Total War: Shogun 2 expansion, Fall of the Samurai was released, we asked Creative Assembly studio director, Mike Simpson about Empire's strange journey. "It's weird isn't it?" he said. "It does keep going – that's one thing about Empire, it's still selling now as much as it was a year ago and that just doesn't stop."

Empire was to be The Creative Assembly's most sprawling, ambitious Total War yet, but its release in 2009 was overshadowed by AI bugs. Passive enemies and weak AI frustrated Total War players. Simpson admits that The Creative Assembly "did take on a little bit more than we were actually capable of delivering by the date."

"We had to have it earlier, so it was buggy on release, and it took us quite a few patches to get that sorted out. But when it was done it gets closer to the product that we originally intended, and it had long, long, long legs."

Empire's vast campaign takes place across three major theatres of war, America, Europe and India. Those are just the land battles, additional coastline zones host naval battles for international trade routes, vital for securing the huge resources needed to fuel a hungry global empire. Simpson described how The Creative Assembly approach each edition of Total War, in stages of "revolution" and "evolution." New titles like Empire are designed to refresh the series and update the engine, acting as a platform for future expansions like The Warpath campaign and, follow-up games like Napoleon.

"Empire was one of those revolutionary steps, but at that point the revolutions were starting to take too long to do, so it started to take more than three years to go around and that cycle was too long," said Simpson. "So at that point we realised you can't actually throw the whole codebase away and start again, we have to do it in chunks. So we're going into more of a continuous revolution process, which seems to be working pretty well."

Empire is available on Steam now for £10 / $19.99, and there's a demo available if you fancy trying it out. It's improved immensely in with the patches CA have added over the years, and there are plenty of mods out there keeping it fresh.

More recently, Total War: Shogun 2 could be considered the next "revolution" of the cycle. We've since had Rise of the Samurai and Fall of the Samurai, which means we're probably due another big step into a new theatre soon. Where would you like Total War to go next?