these 4 include just playing the game to completion,
After beating a few levels (theres only 11 in total) you'll move onto Act 2, Then Act 3, Then the Epilogue.
Basically just play the game all the way through and after beating the epilogue you will have all of these.
Act 1 Completed: Clear Act 1




Act 2 Completed: Clear Act 2




Act 3 Completed: Clear Act 3




Reach The Void: Complete The Game

For these 3 the only requirements is just playing the game again, they're not too hard to get and you don't really need to go out of your way for them either.

Weapon Master: Use All Weapons
There are 4 weapons to use in Post Void; Pistol, Uzi, Shotgun and Knife. When clearing a level you have a chance to change your current weapon to one of the previously mentioned weapons except for the pistol.

Shut up! Give me more?: Spotify: Post Void Playlist
Turn the music slider in audio settings all the way down and you'll get this achievement.



VOID: Die 20 Times
This one is pretty self explanatory, die 20 times.