A unique game that brings a lot with both story and action.
The story is something that kept me on the edge of my seat, much like watching an intense movie at the theater or reading a really engaging book, and I couldn't stop playing because I wanted to learn more about the plot. Throughout the missions a lot of unexpected plot turns will come at you, so expect an interesting story to be presented.
The sounds were great. You could hear the bullets penetrating the flesh of a self-exploding zombie in a peculiar way that made you think "Awesome. Let's shoot moar bullets." That and the fact the action gets pretty sweet when you're getting swarmed by zombies coming out of the ground from all angles and you and your squad are forced to hole up in a certain part of the level.
This is a great game to play in the dark and late at night because you'll really get into the action and light up your room from the blasts of your weapons.
After you progress a bit through the game you're able to take over any squad member, each with their own special powers. With each different squad member comes a different play style, so there's no doubt that you'll find yourself playing one or two members over any other and maybe even ending up hating others. Personally, I liked them all and was pretty well rounded. It also allows you to adapt to the situation yourself and take direct control over the outcome rather than leaving it up to the computer.
The only major gripes I had with the game was the ending, some lack of guidance in not-so-obvious objectives, and the sometimes small levels. The ending which was very hyped and I had high expectations for. It's probably my fault, but just as much the game's because it presents it in such a glorified manner. I still enjoyed the ending and was awed at what happened, without adding spoilers.
A common ridicule in reviews is the small levels. There are a handful of times that this will happen to you, I agree, but you're going to get engrossed in just blasting the hell out of things that it won't matter all the time to you.
There were some parts throughout the game where a squad member or some other would tell you what to do next, or in some cases the game just left you hanging, and you'd have to hunt your way to the next objective. A perfect example that brought me much frustration was the arena during the Roman levels. One, you had to stand on these hidden, tan step stones that were somewhere in the huge arena that was also tan. Two, you had to go through one of the many doors that were spread throughout the huge arena that would be a pain to get to because you had to navigate through traps and more camouflaged step stones in order to activate bridges.
I highly recommend this game to any zombie, horror fans out there. However, don't expect this game to be a lot like any other FPS out there. It's unique by itself and brings a lot for a great action game that'll engross you in its story.