MOB Entertainment had many experimental ideas for making this horror game, many of which were never implemented.
- The factory's exterior is partially modeled at the very start of Chapter 1, even though you start in the reception area and cannot look outside. Combined with an unused objective ("Gain access to the toy factory"), this seems to suggest a sequence where you start outdoors and need to get inside was cut. Other assets related to this, such as a car the player got out of and a parking lot, were left unused in the files. Mob Entertainment would confirm this via a tweet
released on the game's second anniversary. - As shown in this video, the ending of Chapter 2 had slightly different dialogue from Poppy. While she still changes the train's course, saying she can't let the player leave yet because they're perfect for what she needs them to do, Poppy is a lot more upfront and unambiguous with the player about her reasons for doing so, saying she knows they're here to investigate the disappearances of their colleagues and they might find what they're looking for in Playcare. She also says that her existence as a doll killed the player's coworkers, whom she assumes they're here to find. With the Playcare still being teased in the finalized chapter, Chapter 3 reveals that she is still as heroic as the original Chapter 2 dialogue indicated, openly admitting to needing the player's help to kill the Prototype, suggesting the dialogue was only cut to avoid spoiling the game's future direction.
- An unused animation shows that some of Poppy's trailer audio (such as her warning the player about Mommy Long Legs) originally played in an early version of the scene that played after you met her at the start of the chapter.
- The Chapter 2 trailer shows that Daisy the Flower was intended to be the threat in the Musical Memory game instead of Bunzo Bunny.
- The Chapter 2 trailer also shows that PJ Pug-A-Pillar was a more normal-looking purple caterpillar at that point. The files showcase several unused cardboard cut-outs of the various characters, of which Beta PJ is among them◊, albeit with blue added. Another bit of unused concept art also reveals that the character was originally named Cassie Cutie-Pillar. Having been changed to the half-caterpillar and half-dog character in later releases (described as "different and more freaky" by the developers when revealing they were redesigning the character), the leaked prototype went in another direction and showed a version of the final PJ whose body segments were entirely blue, but also covered with blood (similar to a toy found in the final game).
- The files of Chapter 2 contain leftovers from a pretty robust multiplayer mode that was cut at some point. It would've been an asymmetrical mode seemingly inspired by Dead by Daylight and its ilk where up to five players (represented by the dummy mannequins from the GrabPack demonstration tapes) would need to escape the arena while a single monster tried to kill them. Huggy Wuggy and Mommy Long Legs were both playable as monsters, each featuring slightly different abilities. This was later announced, complete with an ARG, expansion to six human players plus the monster, and the introduction of the jack-in-the-box Boxy Boo, as Project: Playtime, where the player is tasked with gathering parts while avoiding the monsters.
- Huggy Wuggy's Trap Breaker ability, presumed to allow him to break traps, was not carried over into Project: Playtime, replaced with an ability to summon Mini Huggies.
- While a series of unused emotes using the hands of the GrabPack made it into the final release of the spinoff, one emote where the hands are used for Flipping the Bird did not make it.
- A storyboard animation by one of the animators showed that after Mommy Long Legs got her hand stuck in the grinder, it was supposed to decapitate her, rather than crush her abdomen.
- The Simon Says concept used for the Musical Memory game was originally intended for Chapter 1, according to unused dialogue in the files of that chapter, but was repurposed for Chapter 2 and its audio redone.
- Kissy Missy's model was also found in the files of Chapter 1, suggesting she was meant to appear in it at one point before being featured in Chapter 2.
- The eyeless statue of Bron the Dinosaur was originally shown in a trailer for Chapter 1, but like Daisy the Flower, was eventually repurposed into appearing in the rejected toys room in Chapter 2 as the statue that the player has to move using an electromagnet. The statue doesn't turn its head to look at the player, as it did in the trailer, but a different, larger, Bron statue in the same room that still has its eyes does it implicitly while the player isn't looking.
- On the Discord server for Mob Games, Micah Preciado revealed that Bron, Boogie Bot, and Cat Bee were originally for a different project, but were then repurposed for Poppy Playtime.
- On May 5, 2023, Mob Games released a special video titled The Lost Secrets of Chapter 2 for the first anniversary of Chapter 2. It showcases concepts that were scrapped or were otherwise unused for Chapter 2.
- The first concept that went unused was you had to follow Poppy before jumping down the conveyor belts, eventually leading you to a power puzzle that would activate an elevator. This elevator would take you to the Game Station. Elliot’s office replaced this.
- Mommy Long Legs had two different sets of dialogue when you encountered her. She even mentions that someone (the name is censored in the video, though it is implied to be Huggy) would warn her that she would have visitors. Her encounter was also more up close and personal than in the final version. Her two previous concept designs were also shown with one of them using folding plastic tubes. It even shows other designs that were more spider-like.
- The Game Station was originally a lot larger and lacked the playground equipment, catwalks, and support beams seen in the final game. It retained the train that sat on a ledge and had four passenger cars rather than three. It also had smiling sun and moon decorations on the ceiling that would have provided light (these had two different designs, with the first looking more realistic and the second having a more cartoony look).
- Musical Memory was originally designed as a room full of TV screens with the buttons working as they do in the final game (only mounted on mechanical arms). It even shows a jumpscare for Daisy when she was going to be the original obstacle.
- Each game was supposed to have a unique factory room connected with them. Only the Molding Room where you create the green hand was kept. Wack-a-Wuggy had a production room while Statues had a quality control room.
- Several other characters were designed to replace Daisy (due to her lacking an audible cue for how close she was to the player) before Mob settled on Bunzo.
- In the trailer for Chapter 2, Wack-a-Wuggy originally planned to have openings from the ceiling for the Mini Huggies to attack, in addition to the holes on the walls used in the final release.
- Also shown in Chapter 2's trailer was that the player originally just directly collected the green hand, and didn't have to get the machine that made the hand to work again like in the final release.
- An unused map for Chapter 1 revealed that the color code used to go deeper into the facility originally was hinted through a series of colored bathroom stalls. This was changed to using a toy train with colored cars in the final release.
- An early version of the room where the player finds Poppy in Chapter 1 starts with the player quickly closing a door behind them, then opening a bookshelf to find a staircase that takes them down to where Poppy is contained in the final version. The starting portion quickly resets back to the player closing the door behind them if they take too long to open the bookshelf, suggesting that the player was closing the door to keep out Huggy Wuggy, who would attack if they didn't escape the room fast enough. The room also has a layout similar to Elliot Ludwig's office in Chapter 2, suggesting it was reworked to become that office.
- An unused office map with several closed gates was planned for Chapter 1 and reworked to become the tunnel area in Chapter 2 where the player meets Kissy Missy and solves a puzzle involving said gates and the Barry cart. The previously mentioned early room with the hidden bookshelf was reworked to fit into this office area, with a trapdoor now being the way to get out of the room.
- According to Marcus Brickley's actor, Sean McLoughlin, he was originally asked to do more lines for the character in chapter 3, implying that he would have had at least another tape focusing on him. However, he was forced to decline due to scheduling conflicts, and Marcus Brickley had no appearance in chapter 3.
- An unused texture of Huggy's face, which is blue-tinted, deformed, and eyeless, was found in the files of Chapter 1. It resurfaced in a prototype map for the Nightmare Sequence set inside Home Sweet Home in Chapter 3 as an early version of the image of Nightmare Huggy's face used in the final map.
- Developer text for different locations where CatNap's shrine would be found if the Toy Store was cut or not suggests that Playcare's Toy Store was planned to be visited at one point in the chapter, even being the original location of the shrine to the Prototype, but was cut and the entrance boarded off in the final release.
- A cut sign for a prison, meant to be seen at the end of Chapter 3 when the player goes down the elevator with Poppy, has been found on an unused map and via developer text, potentially cut as the actual setting of Chapter 4 or for giving away its direction too early.
- Several unfinished areas in the Playhouse in Chapter 3 have been found through hacking the game and are only briefly visible through windows seen while chased by DogDay. The most notable is a swimming pool area with rubber ducky boats. The player can sit in the boat, going through a scripted sequence in which they have to pull levers to advance through the boat ride.
- The character who communicated with the player over the phone was originally named Ace, a grown man with a Southern accent. Like Ollie in the final version, he says he is allied with Poppy and warns the player to avoid the Playhouse.
- Miss Delight's Can't Move While Being Watched strategy originally started with a twist: she would become completely still when the lights were on and move when the lights were off, regardless of whether the player was watching her. This mechanic was present in early access, but cut for balancing reasons in favor of her current functionality, although the Schoolhouse lights still flicker. She also was originally planned to appear in an undamaged form, but while this model is briefly glimpsed during the Hour of Joy tape (used for Miss Delight and her sisters), the low quality of the tape left little room to show more detailed animations. A former animator who worked on her unused model had properly rigged it for animation, suggesting this was how the character was meant to encounter the player.
- CatNap originally had other names in earlier iterations, such as Kuddle Kitty (as revealed in concept art) and Nappy Cat (as revealed in developer text during an early version of the trash compactor map). His skeletal form was also originally going to be a Body of Bodies made from the skeletal remains of humans. The zipper seen along his underside in the final model is also a remnant of a cut idea where taking after Springtrap, CatNap could also be worn like a suit by a human (with the skeletal remains of his human self being hidden inside), using the zipper to go into the toy.
- The orange flare hand originally was meant to have limited ammo, which the player would have to recharge from ammo boxes (with one such ammo box found in the final boss fight with CatNap being meant to be continuously refilled). This was changed to have the hand capable of recharging flares, albeit with a cooldown timer for the charges.
- Several houses for the Smiling Critters cartoon were designed for each Smiling Critter, but in the final version, only DogDay's house is seen.
