Microsoft is serving up a free game to celebrate crossing 300 backwards compatible Xbox games. From now through December 31, Xbox gamers can pick up classic Xbox 360 RPG Lost Odyssey completely free on the Xbox Marketplace.

Lost Odyssey goes free to celebrate over 300 backwards compatible Xbox 360 games

Perhaps more interestingly, this marks the first time the game is available digitally, as it was disc-only when it it originally joined the list of backwards compatible titles. As noted by Xbox's Major Nelson, Blue Dragon, which was similarly disc-only previously, is also now available digitally as a backwards compatible title.

Crossing the threshold of 300 backwards compatible titles is certainly a notable achievement. Perhaps just as impressive is the number of players that use the feature; Xbox's Phil Spencer confirmed this morning that nearly 50% of Xbox One owners are playing backwards compatible games.

If you're interested in scoring a free game, you can grab Lost Odyssey for free at the Xbox Marketplace now. Blue Dragon is also available, though you'll have to shell out $20 to snag it. Still, both are classics that are definitely worth checking out.

See Lost Odyssey at the Xbox Marketplace

See Blue Dragon at the Xbox Marketplace