XCOM: Enemy Unknown has just received a collection of Achievements Unknown. Thirty of them have been added to the game's Steam Global Achievement Page , all showing placeholder names and text. It's another hint that new XCOM content could be on the way, after, last week, a Korean listing appeared for something called "XCOM: Enemy Within".

Firaxis have confirmed that they'll be revealing an unannounced project at this year's Gamescom conference. The number of achievements would suggest that, if it is new XCOM, it will be some form of fairly major expansion. Enemy Unknown's only other additional post-release content, the Slingshot mission pack, added five achievements to the game.

Gamescom starts August 21st, so we'll likely have more details then.

Thanks, Polygon .