Perhaps, the best thing about the FNAF series is the terrific atmosphere. The combination of low illumination, eerie silence, strange sounds coming from mechanisms, and unexpected movements always keeps the player on edge. Sometimes even experienced gamers find themselves scared since danger may appear at any time.
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The other notable element is the diversity of animatronics that behave in different ways. Players should learn how each of them acts to develop special tactics because all of the enemies act differently.
Not only the gameplay of FNAF but also its story attracted attention of many gamers. Many details of the story may be revealed through newspaper articles, hidden notes, calls, mini-games, secret endings, etc.
Instead of revealing all the elements of the story to the players, the game encourages gamers to examine all the details and form their theories about them. Because of that, one of the most active gaming communities was formed around FNAF.