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