Nightmarionne (commonly referred to as Nightmarionnette or Nightmare Puppet) is a secret nightmare animatronic and an antagonist of Five Nights at Freddy's 4. He is among the new nightmare animatronics introduced in the Halloween Edition, alongside Nightmare Balloon Boy and Nightmare Mangle. He is the nightmarish incarnation of The Puppet. Nightmarionne is responsible for replacing Nightmare in the Halloween Edition, and thus shares the same behavior.
He is also one of the non-canon nightmare animatronics released in the Halloween update, along with Nightmare Mangle.
Out of all the nightmare animatronics, Nightmarionne seems to be the "skinniest". He generally appears to bear many resemblances to the original Puppet from the second game. His body greatly resembles to that of a tall human skeleton, being tall and extremely thin. Unlike the Puppet, Nightmarionne's three buttons are absent. The most significant changes are him sporting a large smile full of small, sharp-looking teeth with its upper lip having more teeth than the lower jaw, as well as also being much darker in color to the point of being colorless and sporting longer, even lankier limbs and torso, the latter sporting three sets of protruding ribs. His head structure is very similar to the original Puppet with the exception of lacking rosy red cheeks. His lipstick and tear-like stripes are black in color as well. His three fingers also seem to be longer, thinner, and whip-like each with four white stripes, while the arms are little bit short and lacking stripes. His fingers are divided further down the arm, making them longer and more similar to branching arms. His legs are very long with a needle-like point at the end each, and also lacking white stripes. His white pupil-like eyes are very similar to the phantom animatronics' eyes from the third game, especially when brightened.
Nightmarionne behaves exactly like Nightmare, meaning that he can attack from the Bed, Closet, Left Hall, and Right Hall. Being a replacement of Nightmare, Nightmarionne only appears in Nightmare and 20/20/20/20 from 4 AM on. He can appear in any night with the All Nightmare challenge turned on.
When Nightmarionne is active, the music of the Music Box from Five Nights at Freddy's 2 will play instead of Nightmare's laugh. While sharing the same strategy of Nightmare and Nightmare Fredbear, the player must pay close attention to the music box sound Nightmarionne makes to tell which direction he's going when defending themselves.
Similar to Golden Freddy from the first game while jumpscaring the player, Nightmarionne's close-up screen will appear with light-bluish colors and lack of teeth. In addition to its jumpscare, he shares the same strange radio-like noise as Nightmare.
- Nightmarionne bears a strong resemblance to Jack Skellington from The Nightmare Before Christmas.
- Nightmarionne is the only nightmare animatronic to possess only one set of teeth.
- Nightmarionne and Shadow Bonnie are the only antagonists in the entire series that are completely colorless.
- Nightmarionne is also the only 'toy animatronic' and the Puppet's counterpart that lacks any rosy cheeks.
- Nightmarionne is the Puppet's only counterpart to lack buttons.
- Like Plushtrap, Nightmarionne is a nightmare animatronic without five fingers.
- Nightmarionne only has three fingers unlike Plushtrap who has four.
- Nightmarionne's discovery in its teaser is strikingly similar to how The Puppet was revealed for Five Nights at Freddy's 2; both are covered in near-complete darkness and can only be shown by brightening their respective images.
- The Nightmarionne teaser image was also titled "dontwakethebaby.jpg". This may be a reference to the Youtuber Markiplier, who helped popularize the series.
- Nightmarionne's head tilts towards its right (the player's left) at all times.
- Brightening Nightmarionne reveals that in addition to his glowing irises, he also has spherical shaped eyes hidden behind his mask.
- This can be noted even without brightening, but requires good vision to see as it is very dark.
- Nightmarionne is one of the two nightmare animatronics that are perfectly undamaged, the other being Nightmare Balloon Boy.
- Nightmarionne is the only nightmare animatronic to have thinner, and longer, arms and legs than his original counterpart.
- Strangely, Nightmarionne shares the same sounds as Nightmare (who in turn shares his sounds from his original form as Nightmare Fredbear), from the laughs, footsteps, and even the radio static-like jumpscare sound.
- Nightmarionne, Nightmare Mangle and Nightmare Balloon Boy are the only animatronic counterparts that are not reskins of their original forms.
- Nightmarionne is one of the two nightmare animatronics that don't have any endoskeleton showing, the other being Nightmare Balloon Boy.
- Nightmarionne is the third animatronic with a killscreen, the second being Nightmare, and the first being Golden Freddy.
- If looked at closely, Nightmarionne's left arm is clipping through the wall of the Left Hall.
- This also goes to Nightmarionne's right arm clipping though the wall of the Right Hall.