- Complete Monster: The killer returns yet again. See that page for details.
- It Was His Sled:
- Just like in Sister Location, Elizabeth Afton was Baby's first victim and was ultimately possessed by her.
- Charlie was the real first victim of William Afton, not Sammy. The Charlie seen in all three novels is really an animatronic, given something resembling a soul by Henry's love for his daughter and grief over her death.
- Jerkass Woobie: Elizabeth/Baby. Elizabeth was neglected and abused by her father and then killed by Baby. Baby was initially created to be Charlie's adult body but received none of Henry's love and was later taken and modified by William. The combination of the pair is a bitter, homicidal animatronic still looking for love and approval.
- Moral Event Horizon: As tragic as her past may be, there is nothing forgivable about how Elizabeth Afton/Baby killed Aunt Jen while impersonating Charlie by choking her and ripping out her stomach never letting the real Charlie make amends with Jen.
- They Wasted a Perfectly Good Character: Sammy. Much of Charlie's trauma revolved around losing him and in the Twisted Ones she claimed to feel his presence. Despite the confirmation that William killed Charlie and Sammy is likely still alive, Sammy doesn't appear on-page.
YMMV / Five Nights at Freddy's: The Fourth Closet