Key. (Dark Souls 3)

ThurboCat
You pushed too far somewhere without examining the entire wall.
A key like (the keyword "like") lies near the dogs in a room full of enemies. Also from this room there is an exit to the balcony from which you can jump to the angelic knight. To get into these rooms from the fire in the tower behind the dragon you go to the roof with the black creature. You go down from the roof, go into a room (there is also a Lothric knight with a spear), then you go into the corridor from which the knight came out, go down to the very bottom, kill everyone (there is a fragment of estus in this room, do not miss it if you have not yet taken the wall has a staircase down. There is a dog and a corpse. You lift the key from the corpse.

Eagle-Owl
Thank you 1000 times.

ThurboCat
I advise you to train yourself to search every corner, break every barrel. There are also ghostly walls in the game, they can be where they seem to have no place. Otherwise, you risk missing something that you would not want to miss if you knew about it.