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Right off the bat, let me say, this is a great game! Fun, suspenseful, and Co-Op! If you enjoy shooting zombies, You just can't go wrong here. Hats off to Valve.
Single player and Co-Op (THANK YOU VALVE for bringing it back!!) are great.
Versus… Well, I just don't like it much… Random team, random player? Why the long respawn for the infected? The survivors have far superior fire-power…
What about 32 player Death Match and some CTF?
Alas…
Totally awesome game otherwise, go buy it!