On their way to Reanimation, players will need a door code that can only be acquired after collecting all three memories in Poppy Playtime: Chapter 5.

Players will need to find three friends in the Dollhouse for a tea party, one of whom requires piano puzzle code in Poppy ...

There's a locked door in Conditioning with a strange emoji keypad in Poppy Playtime: Chapter 5, here's how to get the code to unlock it.

Poppy Playtime: Chapter 5 traps players inside a room with Huggy, and they'll need to find three batteries & an optional locker code to escape it.