This is based on opinion. Please don't list it on a work's trope example list.
Nightmare Fuel / Beyond: Two Souls
Entities are scary.
Aiden himself is walking (well, floating) Paranoia Fuel. He's completely invisible and intangible, capable of flying through even the thickest walls, and has a spectrum of powers ranging from Mind over Matter to Demonic Possession. Worse, even Jodie herself has a hard time controlling him when his Berserk Button has been pressed. He could fling tables and knives at you, choke you, make your friend kill you, make youkillyourself... and the only warning you'd have before it was too late would be a chill in the air.
Special consideration needs to be made for the Yť'iitsoh, from its cryptic introduction to the banging noises on the house before we finally see its manifestation as a giant demonic sandstorm that is repeatedly attacking the farm.
And then there is what happens if you linger in the creepy garage for too long.
There's only one Game Over screen in the entire game that happens during Jodie's last fight with the monsters as she tries to reach the Black Sun. Fail the prompts, Jodie dies and the Infraworld merges with Earth, destroying everything in our world and turning it into Hell. And Jodie monologues how she's now trapped alone in the darkness forever with her regrets.
Worse, this actually counts as one of the endings, so you have to let it happen once if you're going for 100% Completion.
This may or may not count, considering it's an Easter Egg, but if you use Aiden on a newspaper-reading man, it shows a headline stating the Origami Killer is on the loose. Could it be that Fahrenheit, Heavy Rain, and this game all take place in the same world?
The entirety of the chapter "The Condenser." A condenser has opened a portal to the Infraworld, and Jodie is the only one able to get close enough to shut it down again. So Jodie has to explore an abandoned CIA facility that is full of dead bodies and dark spirits that have managed to escape from the Infraworld. Then the dark entities start to take over aforementioned dead bodies...
It doesn't help that there's a Jump Scare as Jodie walks through a corridor, a dead body suddenly rises up behind her, but turning around reveals that it's still lying down. The body does nothing for the rest of the chapter, but it's still absolutely terrifying.
The portion of the game where we first find out that Nathan's wife and daughter were killed in a car crash. This is done through Foreshadowing in the form of both of them, with their injuries, repeatedly appearing around Jodie, simply staring at her. We don't even get an explanation of who they are or what they want until Nathan gets the call.
While it's meant to be touching, the part where Jodie helps Stan's wife speak to him through her can come across as quite sinister due to the way Jodie speaks, her exaggerated mouth movements and the fact that she has her eyes rolled up in the back of her head.