I have personally found From Software games like Sekiro: Shadows Die Twice, Dark Souls, and Bloodborne to be just the right kind of difficulty. The games are tough but manageable with time and patience. Some people, however, are just a bit crazy. They want the experience to be even tougher. In Sekiro, you can use an item known as the Demon Bell to increase the difficulty, if that is your thing.
Where To Find The Demon Bell
After fighting, and killing the Chained Ogre, you can grapple up to a hole in the building behind him. Ahead of you will see a group of enemies that you can ignore for now. Head to the right, and use the grapple hook to make your way over the gate in front of you. Drop down and move down the path, and you will find a shrine with a note warning you about an enemy known as “Headless.” Grapple to the tree behind the shrine, then jump down and grab the wall below. Shimmy across to the cave, and venture inside. Go down into the cave, then drop over the ledge into the darkness below. Down here you will find the Headless.
Now, this enemy is tough as nails, so, for now, it is best to avoid it. Move into the back of the cave and you will find another tunnel. Follow this until you come to a note on the wall, with a chalk drawing of a man beside it. Hug the wall at the chalk drawing to activate a secret door. You will enter a short cutscene, and when you exit it, move up the ramp, and you will find the Demon Bell.
How To Use The Demon Bell
To use the Demon Bell, just walk up to it and hit the button prompt to ring it. This will increase the difficulty of the game, and the screen will flash a message that says “Sinister Burden,” and give you an item called the Bell Demon. You can find this item in your inventory, and if you use it, this will return the game to its normal difficulty level.
From my experiments, you can use, and then dismiss, the effects of the bell multiple times. This allows you to toggle the difficulty effectively. While the Sinister Burden is active, enemies will be more powerful, but should also drop better loot!
This should provide a tougher challenge for those who seek it and gives players a good way to change the difficulty of the game if they wish.