Counter-Strike: Global Offensive is the next attempt to refresh the popular shooter after Counter-Strike: Source.
Two teams stand opposite to each other - terrorists and special forces. For every killed oponent we get some money, which we can spend for new weapons or equipment at the beggining of every round.
CS: GO features new maps, characters, and weapons and delivers updated versions of the classic CS content (de_dust, etc.). In addition, CS: GO will introduce new gameplay modes, matchmaking, leader boards, and more.
here is the link that you can buy the game key from it :