Nightmare is the final, ultimate antagonist of Five Nights at Freddy's 4. He is a darker, semi-translucent, and highly aggressive black recolor of Nightmare Fredbear. Lore theories generally interpret him as either a physical manifestation of William Afton's wickedness, a dark variant of Shadow Freddy, or a symbolic representation of death itself claiming the game's young protagonist.

Ennard is a terrifying, spaghetti-like amalgamation of the endoskeletons from all the main Funtime animatronics (including Circus Baby, Ballora, Funtime Freddy, and Funtime Foxy). Serving as the primary antagonist of Five Nights at Freddy's: Sister Location, Ennard schemes to escape their underground facility by scooping out protagonist Michael Afton's internal organs and wearing his skin as a disguise

Michael Afton is the primary protagonist and tragic, undead hero of the classic Five Nights at Freddy's game series. As the eldest son of the series' main antagonist, William Afton, his story centers on a journey of redemption. After accidentally causing the death of his younger brother, Michael seeks to atone for his actions by investigating his father's sinister experiments and liberating trapped souls. This quest leads him to endure horrific trauma—including being disemboweled and used as a skin-suit by a hive-mind of animatronics. Driven by a desperate need to undo his father's dark legacy, Michael acts as the night guard across multiple games and ultimately sacrifices himself in a massive fire to destroy the remaining haunted machines.

Elizabeth Afton is the tragic youngest daughter of series antagonist William Afton. Fascinated by her father's work, she snuck up to his creation, Circus Baby, who accidentally killed and absorbed her. Her spirit then possessed the animatronic, eventually rebuilding herself as Scrap Baby in a relentless pursuit to make her father proud.

William Afton, widely known as the "Purple Guy," is the overarching antagonist and central figure of the Five Nights at Freddy's franchise. As the twisted co-founder of Fazbear Entertainment, he is a serial killer responsible for the "Missing Children Incident". His obsession with the supernatural led him to conduct dark experiments with animatronics, and his soul eventually bonded to the Spring Bonnie suit to become "Springtrap".

Glitchtrap is a malicious digital entity first introduced in Five Nights at Freddy's VR: Help Wanted. Resembling a grinning man in a frayed, yellow rabbit suit, he is widely considered by the community to be a virtual manifestation of series antagonist William Afton's consciousness, or a program called "The Mimic" designed to copy his murderous behaviors. Acting as a computer virus, he attempts to escape the game by possessing unsuspecting human players, most notably a technician named Vanessa, to continue his dark legacy.