Here is the full list of all 46 BURIED STARS achievements.
Fell into eternal purgatory.
Encountered the conclusion of another possibility.
Saw a particular epilogue event after getting rescued.
Encountered the attacker at the site.
Saw all of Hyesung's rapport events.
Discovered the existence of the hidden command center.
Saw the true ending.
Rescued but gave up on truth.
Couldn't take another step before the truth.
Saw all of Gyu-hyuk's rapport events.
Saw all of Juyoung's rapport events.
Saw all of Inha's rapport events.
Saw the first ending.
Changed the Auto-Write message.
Recovered more than half of Mental Gage.
Changed the watch settings.
Listened to a recording file.
Opened the watch menu.
Finished my first recapitulation.
Acquired a new keyword with the conversation.
Began the first keyword conversation.
Played the game for the first time.
You've gone crazy.
Saw all of Seil's rapport events.
Rescued after failing to discover the truth.
Rescued but couldn't complete the picture.
Encountered the attacker unexpectedly.