The library is a strange place to hide a fairy, and the place where she is hidden is even stranger. On the ground floor (with the chatting corner and the tea robot) there is a series of ugly red carpets with gold embroidery. It’s a motive. However, among these rugs is one that is quite a bit larger than the others. If you look closely, you might notice the telltale 90-degree angles of a Holy Cross code.
This one is long but fairly straight forward. Start in any square, then use the directional pad or arrow keys to work your way along the stitched path. If you enter it correctly, you’ll be treated to a light show and your reward will appear in the center of the carpet.
If it doesn’t work for you, here is the code that will make the chest show: Up, Left, Down, Left, Up, Right, Up, Left, Up, Right, Up, Left, Down, Right, Down, Left , up, left, down, left, up, right, up, left, up, right, up, right, down, left, down, right, down, left, down, right.
As a reminder, if you have trouble finding the location, on the “Holy Cross” press up, left, up, right, down, right three sparks that will move towards the fairy.
https://www.gamepur.com/guides/all-tunic-fairy-locations-in-the-library All Tunic Fairy locations in the library