There’s a story behind this picture with a bunch of angry looking zombies running with knives. Developer Mike Booth mentions in a commentary in Left 4 Dead that the concept for the game started with developers playing Counter Strike Source with a bunch of bots armed with knives. They discovered it was a lot of fun and enjoyed the cooperative aspect of the game. The game mode flourished into what is known as Left 4 Dead today. Today that idea comes full circle with the release of CS:GO, in collaboration with Team Plaguefest the game will launch with a zombie mod.
CS:GO is built with the idea of modding in mind. So we can be sure to see lots of community content with the game that will help extend and enhance the game.
Counter Strike: Global Offensive launches next week, August 21st.