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Nightmare Fuel: Siren
Siren/Siren: Blood Curse
"Siren" is quite possibly the creepiest game ever, where out of 10 distinct characters you play as, only the little girl properly survives.
Sightjacking in general. Looking through the eyes of a Shibito gives you not only the ability to see them coming right towards you, but also allows you to hear them talking in their own language...
Even worse: while you're sightjacking, you cannot move. The one thing you do not want to see when you're looking through their eyes is yourself.
The Shibito themselves. In their first form, they look like deranged people, with blood seeping from their eyes. Then they mutate. The first appearance of the dog shibito, spider shibito, winged shibito... Oh, and don't forget the evolved forms of the Onda Twins...
One advert for the game had to be pulled off Japanese TV for being too frightening. The scene in question being Tomoko who having turned into a Shibito ends up screaming for her parents with tears of blood on her face while banging on the window of the church.
There is one boss in the game that you literally cannot beat unless you're prepared to beat it to death with an umbrella.
The music itself is frightening at times.
Only a few characters have access to guns. If you cannot sneak past, or choose to go the action route, you'll need to beat Shibito to death with an umbrella, or a crowbar - that is, if you even have access to a weapon...
More fear is added due to game mechanics; Siren is very vague about what is needed to unlock later levels or to get through the ones you're in. This means you have to go everywhere and check everything - so you have to go into that dark scary shack you don't want to because if you don't, then you might not be able to beat the game. Your map only identifies landmarks which you will need to find; there is no "you are here" marker. Have fun exploring...
In the PS3 remake there is one level in Episode 7 with Seigo when you need to help the little girl escape, you're sniping at first and feel very badass, then you go down and need to find an item but as explained before it is vague to find exactly what you want, so if you open a certain closet you find a freaking head out of nowhere screaming and seeing you, I actually checked the same place in other levels and the head is not there, it is a jump scare but a very good one.
Datatsushi. Not so much in the battle against it, but in the cutscene where you first see it alive, it's terrifying. Oh, and in that battle? It's invisible. You have to sightjack it to figure out where it is from the direction you're facing in its view.
During one of the hospital levels, the only way to survive is to hide inside the incinerator.
Yuri Kishida has a face in her chest. A face that smiles.
There's the boss "Otoshigo." It's mercifully difficult to find a still picture, but there's a video of it here. Be warned that it includes spoilers for the final battle against it.
The scene where Mother is first released and the following scenes of the Yamirei arriving. Seeing those terrifying white wriggling things is enough to frighten a lot of people even without Shu Mikami having been swallowed by tentacles during the same scene. On top of this, their defense against the light involves taking over the bodies of Shibito, presumably killing the Shiryo already possessing them.
The smiles on the faces of the Yamibito.
How about the Yamibito that have giant faces?
Siren: Blood Curse (aka New Translation)
Given how it's on PS3, the update in graphics makes every little thing creepier, such as the locations - more grittiness, more detail, and more disturbing looks on the Shibitos' faces.
The 'Making of' featurette on the disc reveals that all of the freaky movements you see from the Shibito were modeled from professional dancers. Their movements are creepy.
The game-exclusive Maggot Shibito. It's big, it's fast, and it can One-Hit Kill you. It's body is large and thin, looking like a maggot itself, with elongated limbs and legs. The face is horrifically bloated, too.
The redesigns for the Shibito Brains. They have more variaty this time, including one that has four tentacles that allow it to hang, with the rest of the body limply lying there mid-air.
Bella's last level: after exiting a house filled with a family of shibito, you come across the path that allows you to leave the area...then Melissa Gale calls out for her daughter, and you think it's all good, right? Then Melissa comes forward to reveal herself bloodied, with a distorted voice, happy, and says that "I came to get you!" You then have to run around the place, desperately avoiding her grasp.
Melissa traps Bella in the yard by shutting the entrance door and winding the lock tight, meaning that Bella has to get it open again by unwinding the lock while Melissa is searching for her a few yards away. Seems easy enough...until the moment you start unwinding the lock, Melissa can hear Bella trying to escape.
Melissa: "Stop fiddling with that, honey!"
In Episode 6, Howard has to defeat Shibito Seigo Saiga. There's actually detail to Seigo's head, given how he committed suicide by shooting himself in the head with a shotgun; there's a great big hole in the back of his head.
Sam's last level in Episode 12. Melissa bursts through as a Maggot Shibito, demanding her daughter. For the most part, you have to run the hell away from her before reaching several safe spots that allow you to electrocute her through chucking antennae, making sure that you don't fall off while she's circling the place like a predator waiting for its prey. And after that, you have to shoot about a dozen Spider Shibito with a shotgun, taking into account the constant reloading and the fast recovery rate of the Spiders.
The advertising. One of the trailers for the first game featured insanely laughing shibito, as well as some gruesome environments and Gross-Up Close-Up used to full effect.
Then a couple of years later, there was the print ad for Siren 2. A close up of a woman's face. With the eyelids sealed shut. That brought back uncomfortable memories of the trailer, as well as being terrifying.