The 'Man Behind the Slaughter' refers to William Afton, the primary antagonist of the Five Nights at Freddy's franchise. While the character has been part of the lore since 2014, the specific phrase and its associated meme status skyrocketed in early 2020. It centers around a lyric from The Living Tombstone's song 'It's Been So Long,' accompanied by a purple-tinted image or video of the character. The meme often involves turning unexpected objects or characters purple, signaling their secret identity as the villain. It is widely used for bait-and-switch videos and absurdist humor within the gaming and horror communities.