It was okay, but it could have been better. Overall a fun game to play.
Definitely builds up the difficulty during the game. Such aspects include variety of zombies, cult members, and other aspects). But with greater difficulty also provides more ways to overcome that difficulty.
The only problem with the entire game is the way it ends. It has an astounding climax, and then it ends with a question. This game will definitely save itself if it has a sequel, otherwise it is disappointing when you reach the end.