Throughout the game there are a handful of doors which do not do anything, but are required to unlock a specific achievement. There is always a handful of players who ask about where to find these doors, mostly because they already found 3 of them but cannot find the 4th. That's because at least half of these doors are mandatory encounters, and one of them is really easy to accidentally stumble upon. This guide is mostly for the one actually kinda hard to find door, but even then it has been made a bit easier to find. With all that out of the way, we can begin the guide.

The first door is pretty straightforward, and you can access it as soon as you begin Act 1. Simply go to the left of Alice's house, and enter that crypt looking thing. Inside you will find the Death's Door. You can interact with it too. I don't think it's a requirement for the achievement, but do it just to be sure. After interacting with it, we can move on to the next door.

This door is actually a mandatory encounter. You find it at the end of the forgotten mansion. It's in the basement, and is the 2nd door you come across. Not much else to say about it since you literally cannot miss it.

This door is actually pretty tricky to find, and is incredibly easy to miss on a first playthrough. Although it was made a bit easier in an update. For this one, you need to obtain the quest to unlock Gwen. I'm pretty sure this just happens at the start of Act 3, but you'll get a letter from Ludwig asking you to come to his lab. He will send you in the basement to fetch something.

It is also important to note that this is the elevator you need to take, not the other one. The other is missing the option to go to the basement.


Head to the bottom of the basement and you'll see a bunch of papers on this long desk, interacting with one of them will point the player in the direction of the door. It's pretty cleverly hidden, so only people who are interacting with everything are likely to find it. That was until a stain was added against the wall which makes it a little easier to stumble across on accident. Still, quite an annoying door to find considering how easy the rest have been.

I forget if this door is actually mandatory, but I'm pretty sure you have to cross the room it's in to get through the act. It's found somewhere in the Ruined Lab. I'll leave an image of the map so you can quickly navigate to the room. This one can be tricky when trying to backtrack to it, since the Ruined Lab is a bit annoying to navigate.

that should be all of the doors, if you didn't unlock the achievement then you probably did it wrong idk.