Age of Empires Online

The world's as vibrant as it looks, too, with an AI animal ecology meaning that the wild card in your battle with another empire may come in the form of alligators rather than where you stuck your barracks (or it might involve both, of course, if you stuck your barracks near some alligators).

With plenty of missions, most of which support co-op play, and dozens of unique buildings and units, this is looking suspiciously fully-featured for a free-to-play game. So what's the catch?

If you're thinking it must be microtransactions, apparently you're wrong – and Microsoft's even attempting to invent a new word to counter you with. No, the catch comes in the form of "macrotransactions". Rather than whittle your finances down in the death of a thousand cuts, Age of Empires wants you to plump for nice big chunks of content instead. It sounds a little more honest, at least.

We're talking different civilisations for the most part, each with their own tech trees, missions, units, and campaigns. And it's not as bad as it sounds, as the free game should be shipping with both the Greeks and Egyptians available gratis – and that combination was good enough to keep Western civilisation ticking over for a couple of millennia at least.

You'll be able to play co-op for free and enjoy PvP for free too, once you've unlocked your city's arena, which appears to happen fairly early on in the levelling. Upgrading to a premium account, meanwhile – it seems this is done by simply buying a single piece of premium content – will allow you to customise your PvP options. It will also unlock the top level of the tech tree, enlarge your inventory and open up access to rare or epic gear, advisors, workshops or vanity packs for making your city look special.

You can understand holding off of the odd new unit or piece of gear, but putting a velvet rope around the ability to set the parameters for multiplayer matches or issue invites to friends is potentially a little more controversial. It's worth remembering, though, that these are the kind of issues that often get balanced out once a game is actually live, and its players are all screaming their heads off about the same handful of things.

Even with the macrotransactions taken into account, Age of Empires Online looks generous and thoughtful. An eleventh hour developer hand-off from Robot Entertainment to Supreme Commander creator Gas Powered Games may hint at trouble behind the scenes, but the strain, if there is any, doesn't appear to be showing in the content itself.

Microsoft ultimately hopes that this ambitious offering will sweeten the deal for Games for Windows Live users. Whatever you make of that, it's clear that the company hasn't forgotten PC games entirely – even if it is having an intriguing creative crisis regarding what they should look like.