This page of the Ghost of Tsushima guide has all information about playing the flute. This musical instrument has been on Jin's equipment since the beginning of the game. You will learn how to play the flute, how to unlock new melodies, and what are the practical uses of this instrument.
Make Jin can play the flute by swiping left on the touch panel. You can do that right from the very beginning of the game, but this feature isn't always available. It can be temporarily blocked, e.g. during an important part of a quest or when you are attacked by opponents.
The main purpose of playing the flute is to change the current weather. This will only happen if Jin plays the entire tune and you don't interrupt him. Unfortunately, the flute can't stop the storm.
Another interesting use is the ability to play the flute at a friend's grave later in the campaign. This is rewarded with one of the trophies.
Open the equipment menu and select the flute - this will open the melody selection window. There are four tunes available in the game. Initially, the main character can only play the first one on the list.
Each melody can change the weather to the desired one:
- The first tune will summon nice weather.
- The second melody evokes a weather storm.
- The third melody summons dense fog.
- The fourth melody will cause rainy weather.
Unfortunately, playing the flute is not able to drive away the storm, that appeared even before using this instrument.
In order to unlock more tunes, you have to find cages with Singing Crickets. This is one of the collectibles/secrets found in different places in the game world, e.g. in cemeteries or in allied and enemy camps.
You get a new tune after finding several cages. The new tracks can also change the weather conditions.