This game feels more like an expansion than a sequel; however, like its predecessor, it is only a $15 game that goes on sale regularly.
The combat is almost identical to the first. The biggest issue that I've noticed is that it wants to be a co-op "shooter" over a co-op "sniper." There are far less areas for sniping and many more tight corridors and small rooms. There is an addition of stationary turrets in some parts of the game. While we all love a good stationary turret with unlimited ammo to blast zombies with, the machine guns can take from the experience that the first spin Nazi Zombie Army was going for.
A few new enemies were implemented to help mix up the game-play. None of them are ground breaking or innovative, but they do add to the game.
It all comes down to how much you enjoyed the first game. SE:NZ2 is a fun, but it is not an epic title. I personally found the achievements fun to hunt with a group of friends.
One other thing to take into consideration before getting this game is the lack of players. The match making, like the first game, is dreadful. If there are any public players on, you'll be lucky to find a team anyways. Be sure to have a group of friends to play with if you are looking for a good co-op experience.http://steamcommunity.com/sharedfiles/filedetails/?id=200404875