Eidos has now officially confirmed the rumours that Tomb Raider: Anniversary will be arriving on the Xbox 360, albeit it in a slightly different format than expected.

Tomb Raider: Anniversary, which originally hit shelves for the PlayStation 2 and PC, as well as being released on Steam, will be released over Xbox Live Arcade in an episodic format according to press releases from Eidos.

The company has detailed the exact size of the episodes as thus:

"This is the first time ever that the serialization of a full retail game will be available for purchase through Xbox Live® Marketplace. The game will be available in four episodes; Episodes 1 & 2 will be available in September, with the next two episodes arriving shortly afterwards. A full retail version is planned to be released for Xbox 360 later in the year...Additional Tomb Raider Anniversary downloadable content will also become available for purchase on Marketplace to support the launch of Tomb Raider Episodic such as picture packs and theme packs."

The total cost of all four episodes will be 2400 points, which is about $30 or £20, making it a little cheaper than most Xbox 360 titles. We'd expect some extras to be included in either the episodic or retail version to help promote them, but theres little known in that regard just yet, though the Croft Manor area is free with the purchase of any episode.

However, it's not all good news and anybody wanting to download the cheaper, episodic version of Lara Croft's newest adventure will have to own a copy of Tomb Raider: Legend for the Xbox 360, which is a bit harsh for those who picked it up on another platform and will now be forced to wait for the full retail release.

Do you have an opinion on the downloadable content? What do you reckon about the re-imagining of Lara Croft's character and background? Drop us your comments in our forums and prepare for our responses in a staggered, episodic format later on.