Command & Conquer: Generals is a real-time strategy video game and the seventh installment in the Command & Conquer series. It was released for Microsoft Windows and Mac OS X in 2003 and 2004. The Windows version of Generals was developed by EA Pacific and published by EA Games, the Mac OS X version was developed by i5works and published by Aspyr Media. The Mac OS X version was re-released by Aspyr for the Mac App Store on April 12, 2004. In the game, the player can choose from three different factions: the United States, China and the Global Liberation Army (GLA). Generals utilizes SAGE (Strategy Action Game Engine), an extended version of the Command & Conquer: Renegade's 3D engine. An expansion pack, entitled Command & Conquer: Generals – Zero Hour, was additionally released for PC in 2003, and for Mac OS in 2004. Both Generals and Zero Hour were met with highly positive reviews. A sequel, Command & Conquer: Generals 2, was in development, until it was repurposed to a free-to-play game known as Command & Conquer. The new game was part of the Generals franchise and was cancelled on October 29, 2013 by EA after negative feedback during the closed alpha test.