Miki's first night in the house, with its gradual build up from unsettling to full-blown horror when the monster makes its first appearance. She wakes from a nightmare and goes to the kitchen to get a glass of water, where she's grossed out when hair inexplicably comes out of the tap. As she's leaving the kitchen, she hears a strange banging sound in the distance. Upstairs, just as she reaches her bedroom, a door on the other side that wouldn't open before suddenly creaks open. Upon investigating, Miki finds an overturned chair with a strange dark stain beneath it and tucked away in a book a note from her late aunt, the contents of which include disturbing lines such as "they're trying to trap me" and "they hate me". As Miki heads off to bed, she hears a banging sound for a second time, only much closer. Then comes the sounds of something crawling down the hallway, before the monster finally bursts on the screen, growling demonically. It then slowly begins making its way towards you as images of the monster's face flicker across the screen, becoming larger and more vivid the closer the monster gets.
The monster. It's a grizzled, zombie-like creature that crawls along the ground with its arms due to having no legs, though dont think its slow because of that. And that's just the sprite. The close-up images of the monster's face reveal it to be a bloody, rotting skeleton with a gaping maw and staring eyes. As it moves, it makes a horrible slithering, squelching sound and utters unnerving rasps and growls, reminiscent of the death rattle uttered by Kayako in The Grudge films.
In the 2019 remake, the monster no longer looks like a zombie, but something similar to The Crooked Man instead, a blurry, dark figure of a woman with a broken neck. Say, didn't Miki's aunt Saeki die from hanging herself...?
There is no music in the game, just in-game sound effects. The long periods of silence can actually make for a more unsettling atmosphere, as you don't know what will happen next or when it will happen. It also underlines just how isolated you/Miki are. During the chase sequences, instead of music, there are strange, whispering voices and eerie breathing heard in the background, which add an extra layer of creepiness.
The hints throughout the game and especially the revelation in the Good Ending that Miki has schizophrenia can be rather disturbing, as it's unclear if any of supernatural events are really happening or are just delusions Miki is having. She's the only one who ever experiences the so-called hauntings after all and her mentally-ill aunt Saeki had similar experiences before her death. Near the end of the game, Shinji strongly suggests to Miki that the hauntings could just be a product of her imagination. Although they feel very real to Miki, even she seems uncertain at this point. If she tries to tell her mother about it, she just mocks her for being "crazy" and even says she should kill herself. Regardless of whether or not the monster is real, Miki has effectively been abandoned in a very vulnerable state, which is terrifying enough on its own.
In the Bad Ending, upon entering the final locked room and seeing the monster hanging from a noose, Miki stands there, refusing to run and repeatedly insisting it's not real, as the monster drops down and advances on her. The monster rushes at her and the screen goes black...a newspaper clipping then reveals that Miki was found dead in her home the next day. We are not told what exactly happened to her.
The 2019 remake makes things worse. When Miki's body is found, they find her dead of apparently self-inflicted wounds, suggesting a Through the Eyes of Madness account. Also Miura starts blaming himself for not noticing Miki's decaying mental state. As he's lamenting, the monster looms behind him, implying that the story will repeat once again.
The chase sequences, which are also some of the most notoriously difficult parts of the game. You can't fight the monster and have to run until you find a place to hide. Trouble is, there are only two valid hiding spots in the house on any given night and these hiding places are randomised every time. Two other hiding places lead to instant death, while the others will result in you being found, but you'll have a chance to get away and keep running. The monster is only just slower than Miki, so making one wrong move or accidentally running into a room with only one exit can easily be fatal, and are pretty easy mistakes to make as you race around desperately trying to find a hiding spot before the monster gets into a room with you (understandably, you can't hide after the monster's already in the room). Once you have found a hiding spot, the screen goes completely dark and for several seconds, the only sound is Miki's laboured breathing as waits to see if she's been found. Just when you think it's been long enough that you might be safe, the monster may suddenly Jump Scare you with a hair-raising growl.
In the original game, the monster only appears in the house and garden to terrorise Miki and she seems safe elsewhere. In the remake? The monster even follows her around town, meaning nowhereis safe.