Folding Screen Monkeys are the major boss in the Sekiro game. They are located in a special area near the Senpou Temple. You will earn some rewards after killing all of the three monkeys.
You can counter the Folding Screen Monkeys by following the below steps.
How to defeat Folding Screen Monkeys:
The first thing you need to do is to open up the dark roam. Head towards the Senpou Temple and look for the dark gate. Once you find the dark gate, just open it.
Return back and jump on to the big tree. Ring the bell to stun the green monkey and then kill him only with one deadly strike.
Go to the dark room again and you will find a purple monkey there. Just kill him with your lusty blow.
Return back again to the starting point and make your way into the wet room which is located on the right side. Follow the footprints and jump on to the roof of the temple. Just slowly move forward towards the red monkey and then kill him.