YourEMGN writes: "Is it a sequel or a late expansion pack rip-off by Valve? We find out.
Left 4 Dead 2, just like the first game continues the aftermath of an apocalyptic pandemic in which players must guide the 4 ’survivors’ through the level into the safe house. On the way, you will encounter hordes of infected zombies. Unlike the previous title, Left 4 Dead 2 actually has a story which adds a bit more value to the sequel. The question on every ones mind, is it worth being called a ’sequel’ or is it a late expansion pack?"
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The Lowdown on Left 4 Dead 2