Potential identity of the player (spoilers ahead)
I think I may have figured out a potential body for who the player character may be, with hints providing for this. I am on mobile so I apologise for any weird layouts.
So in poppy chapter 4, we discover a tape in the warden’s office of the warden bargaining with the doctor for his freedom in exchange of the omni-hand during the hour of joy.
The player was also one of the few, if not the only surviving employee from the time of the hour of joy, from either escaping, or not showing up (which I honestly kinda doubt, as when they hallucinate during chapter 3, we hear the screams of the hour of joy before presumably learning what it is. With this, I believe the player may be the prison warden.
Why do I think this? Well, I’ll lay it out here. First, the toys recognise the player. It’s unlikely that they’ll have returned wearing their old uniform, meaning they have to recognise the players face, something they’d have to have seen a lot of, someone who may have been in a high power. Second, the player is shown to have returned out of guilt, either for abandoning his colleagues (as shown in the letter, they are told they are still there), or for knowing what happened to the kids in relation to the experiments and the bigger bodies, something they would have had to keep housed in the prison. Third, they’re well skilled in defending themselves with a grabpack. They have fast reflexes, precise aim and know how to handle different forms of hands. Something they would need to know in case a riot or breakout was to occur. Fourth, they happen to know almost exactly where to find the omni-hand, as if they were the one that put it there, something we know the warden did to secure his freedom.
Now I know this idea might be filled with holes and plot points I’m missing, I’m not too caught up on the lore, especially he book, but it’s just an idea I came up with when watching that tape and playing the game again.