It’s pretty easy to miss the fairy location in Tunic’s eastern vault. When you skew there, go straight south and down the main stairs. Head west until you reach the room with all the guards inside. Once you’ve submitted them and have some privacy to solve puzzles, it’s time to get to work.
Direct your attention to the energy node that you have activated here for the first time. Now it’s just a gray square on the ground.
Notice the candlesticks around the knot. If you have solved the tree puzzle for a fairy in the Western Garden or the well puzzle in the overworld, you will know the solution. However, if you haven’t, make a note of how many candles belong to each cluster. One and four on the right, three on the bottom and so on. You must count each group of candles with your Holy Cross (D-Pad on a controller, arrow keys on a keyboard). So you push right first because it has the cluster of a candlestick. The one on the left would be second because it has a group of two candles. And then you continue in this pattern.
Still not working for you? Here’s the solution: right, left, down, right, up, left.
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-eastern-vault All Tunic Fairy locations in the Eastern Vault