Five Nights at Freddy's Plus was an official re-imagining of Five Nights at Freddy's originally developed by Phil Morg as a part of the Fazbear Fanverse initiative. It was intended to serve as Phil's re-imagined take on Scott Cawthon's original Five Nights at Freddy's game. 

Links
Trailer
Download
Legacy Download*

*The original files used for 3MUG before the revamp, essentially older versions of the game.