The Nightmaretaker: The Man Possessed By The Devil — Guide |link|

The entity grows stronger the longer you look directly at it. Keep your camera angled downward during encounters. Essential Survival Strategies

It sounds like you're referring to a title or concept related to horror, folklore, or possibly a game or story—perhaps a mix of "The Nightmare" and "The Nightmare Taker" or something like The Conjuring or The Exorcist themes.

Most versions of the game require you to collect specific items (idols, pages, or candles) to exorcise the entity. the nightmaretaker: the man possessed by the devil guide

If this is for a sandbox game:

Furthermore, Silas Vane (the human remnant) fights back. Vane hides "exit doors" inside the nightmares. These appear as out-of-place doors—a bright red door in a grey hallway, or a door painted with a white eye. Opening this door ends the visitation instantly. This is why the Nightmaretaker moves slowly. He is fighting his own possessed body. The entity grows stronger the longer you look directly at it

The most dangerous. The Nightmaretaker sits in a rocking chair and sings a lullaby in Latin backward. If you fall asleep within the dream (a nested nightmare), your soul remains in his pocket watch, and your body enters a catatonic state known as "The Caretaker’s Fade."

The man and the devil are no longer separate; their desires have merged. Most versions of the game require you to

Something that hooks fans of psychological horror.

Understanding the "why" and "how" of this possession is key to the lore. The devil, in this context, rarely takes over a strong, righteous person. Instead, the man possessed by the devil usually shares certain traits. The Stages of Possession

Attach the handle to the main pipe assembly in the Ritual Room.