Here is the full list of all 28 Causality achievements.
Save over 10 times.
Get chased by ghosts for more than 1 minute.
Stay next to a blind ghost for more than 30 seconds.
Use canned coffee at least 5 times.
Witness five types of Poltergeist.
Walk 100 slots in a row.
Meet 2 different ghosts in a row without being noticed.
Don't get attacked, even once, after being chased by the Shadow.
Don't get attacked, even once, after being chased by the Black Hand.
Don't get attacked, even once, after being chased by the Skeleton.
Don't get attacked, even once, after being chased by the Spider ghost.
Don't get attacked, even once, after being chased by the Eye.
Don't get attacked, even once, after being chased by the Specter.
Don't get attacked, even once, after being chased by the Multilateral Spirit.
Don't get attacked, even once, after being chased by the Han-am Spirit.
Ditch a ghost at the bathroom divider.
After solving the 3-1 class puzzle, ask how to use the bolt cutter you obtained.
Save once, and witness the true ending.
Get the electricity back on, and save for the first time.
Rescue the first student.
Rescue the second student.
Open the shutter to the annex.
Get the rooftop fire shutter key.
Escape from the final ghost.
See the normal ending.
See the true ending.
Make all the noise in class 2-4.
Use the 2nd Floor fire shutter key.