Xcom: Enemy Within will be heading to PC and Mac as a straightforward DLC download, but Firaxis explained to us at Gamescom the reason why console gamers will need to buy a disc-based edition of the expansion (called the Commander's Edition) - it's simply too big to be downloadable content on console.
"For the expansion on the PC, it was fairly straightforward," senior producer Garth DeAngelis confirmed to Joystiq this week. "When it came to the consoles, it was too big. If we wanted to deliver the same content to the console players, we had to do it this way as a standalone expansion on a disc. We couldn't simply just patch it in."
On top of the new content and existing DLC (the base Xcom: Enemy Unknown game, the Slingshot and Elite Soldier add-ons, and Enemy Within are all included), the Commander's Edition will also include new units, upgrades and skill changes.