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.
Use the snake ring at the best place.
Get the fire room letter without using the bucket of water.
Enter the fire room from a secondary door.
Find the castle's wall at day.
Find the chest hidden near your house.
Find some stale bread before night falls.
Kill the old woman and Eisbein.
Get the treasure hunter badge from Giulia.
Find the hidden treasure of the Count.
Catch the butterfly in the depths.
Discover the truth in the throne hall.
Guess the kobold's name without using the letters.
Open the garden chest.
Feed the worm from the depths.
Guess the kobold's name using the letters.
Catch Eisbein.
Find J.F.'s most important note.