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