Developer: Valve Released: 2009 Platform: PC, OS X, Linux, Xbox 360 The first Left 4 Dead game quickly put to rest any initial complaints regarding Valve's priorities in game development, thanks to its hugely entertaining online co-op action and cleverly designed 'AI Director'. Left 4 Dead 2 arrived only a year later, and has since managed to make the first game just about obsolete. Left 4 Dead 2, in its standard mode, brings four players together in a team, as they battle through a series of zombie infested levels. The first-person shooting action is as tight as you'd expect from the developers of Counter-Strike, while the AI Director 2.0 manages to keep things more tense and exciting than ever. Because each encounter is semi-randomised depending on the progress of the survivors, Left 4 Dead 2 is immensely replayable, and still has a thriving community almost five years later. An improvement on the first game in almost every way, Left 4 Dead 2 is a must-have for any zombie-lover's Steam Library.
