To celebrate the one-year anniversary of its backwards compatibility programme Microsoft is giving every Xbox One owner a completely free game. What's more, you don't need to be an Xbox Live Gold member to download it, you just need to make sure you redeem it soon as it's a limited offer.

So here's what game is on offer and how to redeem it.

The giveaway is one of the 300 plus backwards compatible Xbox 360 games that you play on an Xbox One. It is the Japanese RPG Lost Odyssey, which came out exclusively for the Xbox at the beginning of 2008 (in Europe and the US) and was much acclaimed back then.

MicrosoftLost Odyssey

That's because it was designed and co-written by Hironobu Sakaguchi, the creator of the Final Fantasy series, so very much echoes his other, better known games. It also has a turn-based battle system so will feel very familiar to fans of JRPGs generally.

You play as Kaim, an "immortal" who leads a party of fighters as he attempts to regain his memories and generally save the world as it goes through a magical industrial revolution. It's a lengthy quest and there are plenty of random encounters along the way.

There are a few ways you can nab the free copy of Lost Odyssey. Head to the Xbox store website here and you should find a link to "buy" the game. It won't cost you a penny though.

Alternatively, you can "purchase" it through your Xbox One by heading to the games store on the console, search for Lost Odyssey and follow the instructions on screen.

Finally, you can also get it through the Xbox apps on mobile or desktop.

Once you've downloaded Lost Odyssey it's yours to keep forever and will be permanently linked to your Xbox account. However, you do need to redeem the game before 31 December 2016. After that date it will return to its original price and you'll have missed your chance.

You can find an entire list of the games available through backwards compatibility here. The vast majority of them are available to buy digitally through the Xbox store. You can also use an existing disc version if you have one lying around.

Sections Microsoft Xbox Games