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"User Rating 7.9/10, Metascore 83/100. Counter-Strike: Global Offensive (2012) (PC), Counter-Strike: Global Offensive features new maps, characters, and weapons and delivers updated versions of the classic CS content." source metacritic.com
"User Rating 8.9/10, Metascore 88/100. Counter-Strike: Source (2005) (PC), Valve has taken a large selection of the maps from Counter-Strike 1.6 - Office, Havana, Italy, Aztec, Chateau, Cobble, Piranesi and of course eternal favourites Dust and Dust 2, and recreated them for the source engine. This means all new textures and major aesthetic changes with more complex buildings and scenery. In addition, the levels are scattered with objects that react realistically with the Source engine's physics engine. The game is available through Valve's Steam downloading service and is distributed with Half-Life 2." source metacritic.com