There's a quote that's attributed to Plutarch, although actually from Die Hard villain Hans Gruber: "And when Alexander saw the breadth of his domain, he wept, for there were no more worlds to conquer." Well, the developers of Anno 2205 have solved that problem: if there's no land left on Earth, go to the moon instead.

Space travel is one of the big gameplay changes that Ubisoft's bringing to the sixth installment of the long-running strategy/city-building series. As one of Ubisoft's developers said, the last entry in the franchise, Anno 2070, did so well with its near-future setting that the company felt like returning to the series' historical roots would be a step backwards. The only way to move forward is to push Anno 2205 even further into the future.

That means moon-based settlements, as well as bigger and more expansive Earth-based cities, as well. When the Ubisoft dev talks about Anno 2205, he uses the word "epic" a lot. Thankfully, the game backs that up. Anno 2205 is still in alpha, so the game still occasionally stutters and drops the occasional frame, but even in this early state the game is convincingly huge.

Essentially, Anno 2205 is divided into a number of different "sessions," or sprawling, living plots of land, all of which progress in real-time. Some sessions are on Earth; others are on the moon. Players can open up any of these sessions and build to their hearts' content, but they won't want to focus on just one or two. Different sessions have different resources, and in order to fully upgrade buildings, players will need to set up trade routes between them.

Every session has its own unique topography and style, and each one presents its own set of challenges, too. For example, while Earth-based settlements can set up farms, moon colonies need to establish more sophisticated greenhouses to generate food. The moon's a much harsher setting than Earth, too - meteor showers are a constant threat, and players will need to build expensive force fields to protect their citizens. In some ways, it's almost like having multiple Anno games in one title.

It's Anno 2205's scale that's really impressive. Without actually showing footage, it's hard describe exactly how large each session is. The Ubisoft dev wouldn't say how many sessions the game supports in total, but there were at least eight on the demo screen (although most were hidden behind question marks). Taken altogether, and Anno 2205 has enough content for literally hundreds of hours' worth of play time.

With a game this big, Ubisoft's developers need to be careful that the interface doesn't become overwhelming, and with Anno 2205, the engine's getting a big overhaul. Instead of inundating players with numbers and text, Ubisoft's trying to deliver as much information as possible visually. If citizens are happy, they'll roam the streets. Crowds will roar in the local sports arena. If they're unhappy, players will see people vacating buildings. Menus are all image-driven, and status messages appear as flashing icons, making them easy to see.

While settlements start small, they grow quickly, and compared to games like Sim City, Anno 2205's sprawling metropolises are lush and incredibly vibrant. In fact, the detail is probably Anno 2205's most impressive feature. Players can view cities from high in the air, or zoom down to watch individual citizens milling around. In happy cities, some will be pregnant. Players can also jump around to pre-set cameras anywhere in the session, and it'll appear on screen instantly. Even at this early stage, there are hardly any loading times.

Unlike past Anno games, in Anno 2205 there's no difference between the story mode and the infinite game. Previously, the story mode acted like a tutorial; once it was finished, players were forced to move on. Unfortunately, Ubisoft says, players often grew attached to the first things they built, and didn't want to abandon their early creations. In Anno 2205, the story and free play are intertwined. Those who want to focus on quests can; those who don't can ignore them. Either way, players won't have to start over.

Ultimately, it's that kind of flexibility that Anno 2205 development prioritizes. The large worlds offer a variety of different options for gameplay, while the visually-oriented interface should provide a low barrier of entry, welcoming casual and hardcore fans alike.