Here is the full list of all 27 The Cave achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Saw the darkness in all our hearts.
Collector of forgotten dreams.
The scale reveals a baleful figure.
Peered into everyone's fate.
Stood by and watched as the Twins murdered their parents.
Watched Mummy and Daddy's furniture get broken all to bits.
Everyone reached the bottom.
Saw the good in everyone.
Remembered it's wrong to steal.
Played some dubious role in the Monk's murder of his Master.
Broke bridges.
Shared in the blame for the Scientist's act of mass murder.
Slipped, where wet.
Came ever-so-close to recovering the Sarcophagus.
Pantomimed an ancient hieroglyph.
Reached the bottom of The Cave.
Food-based destruction.
Recorded and played back the elevator music from the Zoo food court.
Served as an accessory to the Time Traveler's murder of her enemy's ancestor.
Made all three characters smell like a dinosaur at once.
3 die by the Miner's hand.
Enabled the Hillbilly to burn down the Carnival.
Where did the King go anyway?
Helped the Knight obtain Excalibur.
Saw a postcard stolen from the Gift Shop.
Sacrificed oneself for ultimate flavor.
Got everyone out of The Cave without dying once.