XCOM: Enemy Unknown's expansion, Enemy Within, will be issued as DLC on PC and Mac for $30, but the only way to get it on consoles is through a new Commander's Edition - a retail re-release that includes the XCOM: Enemy Unknown game, the Slingshot and Elite Soldier add-ons, plus the Enemy Within expansion.

The reason for issuing the Commander's Edition is because Enemy Within is simply too large a file to patch into the console game as DLC. "For the expansion on the PC, it was fairly straightforward," Garth DeAngelis, senior producer at Firaxis Games, said during a PAX Prime interview. "But 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."

DeAngelis added that Enemy Within includes so many changes to the base XCOM: Enemy Unknown experience - new unit types, upgrades and even skill changes - it necessitated an entire re-issue of the game. "These things are tied deeply into Enemy Unknown so we wanted to release [the Commander's Edition] as sort of the ultimate edition, with all the previous DLC on this one disc. It was either deliver it this way or not deliver it at all."

XCOM: Enemy Within, announced at Gamescom nearly a week ago, launches on November 12.