Categorised list of achievements with tips and useful information.
Normal Progression
Taking Photographs
From start to finish, unlocking every photography achievement could take an hour or so. By playing the game normally and taking other photographs here and there, you may already be half-way. Track your progress in the pause menu.
Don't forget to remove all unnecessary photographs afterwards. The fastest way to do so is to expand any photograph and press open containing folder., then selecting and deleting all unnecessary entries.
Don't forget to remove all unnecessary photographs afterwards. The fastest way to do so is to expand any photograph and press open containing folder., then selecting and deleting all unnecessary entries.
Level Secrets
Prologue. Get ran over by a car.
Garage. In the back of your car, there is a flashlight that can be picked up. Take it.
Theater. Start every projector which can be switched on by pressing 4 buttons.
School. In the room which unlocks with the red key, containing the blue key, on the back of it, there is a wall with blood stain on it. It is a hole in the world, enter it.

After falling out of the world, you will appear in a maze. This is a partial layout, in case you get lost:

The achievement unlocks once you fall out of the maze.
Locked Doors
There are locked doors in some of the maps. Unlock codes are written on newspapers hidden on other maps along with text that hints on which map they are to be used.
Code hidden in Hotel: 738025. Unlocked in Garage. Thanks Notsew.

Code hidden in School: 040723. Unlocked in Metro. Thanks voso.

Code hidden in Mall: 011323. Unlocked in Hotel. Thanks Nomnom.

Code hidden in Garage: 051285. Unlocked in Mall. Thanks the amazing phlog.
Code hidden in Hotel: 738025. Unlocked in Garage. Thanks Notsew.
Code hidden in School: 040723. Unlocked in Metro. Thanks voso.

Code hidden in Mall: 011323. Unlocked in Hotel. Thanks Nomnom.

Code hidden in Garage: 051285. Unlocked in Mall. Thanks the amazing phlog.

Hidden Anomalies
Take photographs of each hidden anomaly. Track your progress in the pause menu and the gallery.
For some help, refer to GreenoSylveon's guide:
https://steamcommunity.com/sharedfiles/filedetails/?id=2965374159
Conspiracy Report unlocks Museum, where all other related achievements are obtained.
After the credits of the secret ending, press the cryptid hunter. button in the lower right corner. If you miss it, it is possible to play Cryptid Hunter from map selection screen, the Minigame map. The achievement is unlocked if you win the minigame.