Here is the full list of all 32 The Count Lucanor achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Discover the truth in the throne hall.
Catch the butterfly in the depths.
Feed the worm from the depths.
Guess the kobold's name using the letters.
Kill the old woman and Eisbein.
Find J.F.'s most important note.
Use the snake ring at the best place.
Enter the fire room from a secondary door.
Find some stale bread before night falls.
Find the chest hidden near your house.
Find the castle's wall at day.
Catch Eisbein.
Guess the kobold's name without using the letters.
Open the garden chest.
Find the hidden treasure of the Count.
Get the treasure hunter badge from Giulia.
Get the fire room letter without using the bucket of water.