Here is the full list of all 18 Between Me and The Night achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Complete level 3 of Generic Knight.
Finish the game.
Listen to all the cassettes.
Finish the apartment level.
Clean up the broken objects in the apartment.
Find the 3 strange medicine bottles.
Finish the high school level.
Complete the Thunder Rangers poster in the High School.
Get to the end of 1000 Knights.
Let the Keykeeper catch you while holding the hall pass.
Don’t get hit by enemies while in the Otherworld.
Finish the house level.
Complete the house without being caught by any ghost.
Put all the soldier and knight toys in their respective bases, in the House.
Enter the Otherworld for the first time.
Finish the tutorial.