As of December 2015, Ubisoft pulled R.U.S.E. from Steam due to the expiration of the military license, thus the game is no longer sold for PC. However, the game is still available on both the Playstation 3 and Xbox 360 via digital download. More information here: Kotaku, PCGamesN.
The Chimera Pack was the second DLC pack for R.U.S.E., released on January 18, 2011. The Chimera Pack breathes new life into both multiplayer and solo skirmishes.
First, players will be challenged in 3 new multiplayer maps, with a real change of scenery. Solo mode has not been forgotten, with 3 exclusive challenges: Bir Hakeim drives your army into the Libyan desert, where the Free French Forces resisted the AxisAdvance in 1942. You will also play a part in a fight at Majaz al Bab as well as the Zapad operation.