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Nightmare Fuel: Ōkami
Ōkami. A game where you are a goddess stuck inside a wolf's body while fighting off demons, monsters, the fearsome Yamata no Orochi, and Darkness personified. Between the Video Game Caring Potential and the comedy in this game, there lurks scary, terrifying stuff...
The Ghost Ship
Players are at one point required to visit the haunted wreck of a treasure ship. In one part of the ship, a massive, gasping, sea-weed covered face can be seen sticking out the water. While you're in the water, it summons forth massive hands that rise up out of the murky depths and try to grab hold of you. Getting out of the water doesn't really help either; more hands reach out for you in a variety of uniquely creepy ways. Still, getting to kill it while it was weak and vulnerable almost made the trauma worthwhile...
In the same place, there is also a pair of little girl dolls. A player will regret power-slashing them.
That place also had the deadly spirits of a couple-turned-fish monsters, who combined into what one can only describe as a scarred, monstrous orca whale-sized great white shark. If you have an incredible fear of deep water, especially with fish that easily dwarfs you, finally killing it brought huge relief.
The ghosts. Okay, so it's just a few imps, just try and go around this and- Spider Queen in your face, with the screech she makes as well. Furthermore, the prayer slips that exterminated ghosts up to this point are completely ineffective.
What's scarier is that even after the player tries to use the Celestial Brush, an action that normally freezes all gameplay, the Spider Queen will continue her ghastly in-your-face, screen-filling floating. The only way to get rid of the ghost is to just wait until it leaves.
On the topic of ghosts, that giant chattering skull of Crimson Helm that keeps coming at you even when you're trying to use the brush. It also looks like it's trying to chew on you when it's hovering over you.
And the Chest Monsters. If only they would come to life when you were a polite distance away, instead of right next to you. Furthermore, this is the only place in the game to have them, leaving you paranoid of further Chest Monsters.
It gets worse in Okamiden: you actually spend a fair amount of time on the ship before it sank and you witness it getting destroyed by the Water Dragon. Imagining all the people there becoming monsters.. yeesh...
There was also the ancient ruins in the forest where you fought your first boss; it looks nice, seems rather peaceful...then you hear the music.
The Spider Queen herself. The eyeless face, the backwards-looking hands, and her habit of suddenly rushing the screen at terrifying speed, as well as the screeches she makes when you Power Slash/use slips on her eyes.
Mr. and Mrs. Cutter live in a decaying house, surrounded by a cursed aura, complete with creepy music, even after you restore Taka Pass. Get too close during the day, they'll try to catch and eat you. At night, you can go inside, where she's sharpening her knife and he's talking in this sleep ("I'm... so hungry... Guuurgh...").
The sky changes ominously from clear blue to bloody red when one gets too close, even at night.
The Evil Rao reveal. Specifically, the way her face moves while she's talking, eyes included - but the glowing red pupils don't.
And then finding the crusty old body in the well when the ghost leads you in.
The corrupted valley and forest early on in the game. That thick mist and darkness that slowly saps your health, not to mention the creepy music playing.
And Kusa Village during the first visit. Even after restoring Taka Pass, it remains cursed, and the entire place is like one big, dark Cursed Zone. Ammy's ink drains, leaving her virtually powerless, and players can barely see anything that is, in-game, a couple of feet away from Amaterasu.
The Water Dragon. The first time you see it is when you leave the sunken ship...and chances are you won't be able to escape before you find yourself back on the beach. After that it roams the water, and it's so massive that you can see it if you stand on a certain cliff/the edge of the beach. If you don't ride Orca into the whirlpool it'll chase after you and try to eat you.
The fact that he's based on an Oarfish doesn't help either...
And the music goes into a creepy minor key if you swim/walk too close to him.
There's a part in the game in which you must enter the belly of the water dragon. The fact that the inside of the dragon's belly looked more like a place with cliffs, waterfalls and islands, complete with strange trees, actually manages to be somewhat disturbing. Power Slash the "trees" and they bleed.
In some places there are skulls that you can break to get money, health, etc. This is fine when you break them with a headbutt. When you break one with a powerslash, the skull's eye sockets light up and it opens its mouth and laughs before spitting out your prize.
The evil door locks that creepily laugh at you when you come near them. And when you find the key, after they seem to be freaking out at the sight of the key, it goes through their eye.
You think that's bad? Try Power Slashing them. They make a noise that's ... indescribable. It doesn't help that they utterly lose it when you do that.
While also a candidate for Best Boss Ever, the battle with Lechku and Nechku was one of the creepiest things in that game. Unlike most of the bosses, they don't really speak to you, they float around with their heads twitching, You can hear their clockwork ticking and occasionally their hoots amongst the epic battle music.
When you first meet one of them, it has its back turned to you. Then, in a series of erratic jerking motions, it twists its head around 180 degrees to look right at you.
When both of their clocks reach 12, time just stops, and the colors are reversed. Then, Lechku starts slowly walking toward you.... It looks like you need something complicated to fix that, but you don't. It's just Powerslash. But, God, does it scare the ever-loving crap out of you the first and only time it happens.
Climbing Cat's Call Tower the first time could count. Even when you haven't entered the area to climb, if one even gets near that island, that sound... the meowing... keeps echoing over and over. It's probably not good to look at either for people who are afraid of heights...
The enemy gallery is made up of very detailed calligraphy drawings of each enemy, complete with hideous faces and grotesque details not visible in-game. Images range from an overly graphic fish-woman in a kimono, a flaming wheel with a grinning mouth in the center, and a drawing of Orochi that appears to be bleeding heavily.
The Gashadokuro in Ōkamiden, massive skeletons rising out of the ground, with a burning jewel in their ribcage protected by a pair of swords which they occasionally pull out to try to kill you with. According to the bestiary, they're made up of the bones of murder victims.
Truth in Television: they really came from Japanese Folklore, murder victim's bones and all. Oh, and the original ones had the habit of biting their victim's head off.
A-A-Amaterasu, save us....
Anything that keeps moving even when you've got the Celestial Brush screen open. Normally the screen is completely paused, so you feel free to edit the world at your leisure, but enemies that keep moving, or keep coming at you, can really get under your skin and make you feel defenseless. In the same vein, trying to use the Celestial Brush against Ninetails, only to see him start drawing.
Yami. At first, he's seems to be simply a giant sphere with weird symbols, but it gets worse when you think about it. He manages to stand out like a sore thumb due to the fact that unlike everything else in the game, he looks cold and realistic rather than the bright and lush art you've gotten used to. He's portrayed as a force of pure malevolence rather than an actual "character" Furthermore, his back story is about next to nothing; all we really know is that he killed an entire race by himself, and he seems to be related to the Moon Tribe somehow. His final form is essentially a demonic claw, and his true form is that of a small fetus-like being. One terrible thing to notice is that he has blue Facial Markings that are just like Amaterasu, suggesting that he is also related to the gods. His powers are essentially that of a Lightning BruiserMagitek tank, which no other enemy is like aside from Lechku and Nechku. Worst of all, he seems to have the power to randomly destroy Amaterasu's powers, and if it weren't for the fact that Ammy had just entered her Super Form, it's very likely Yami would have slaughtered her easily. All in all, the questions of "who is he?" "where did he came from?" and "what does he want?" is enough to scare anyone who was thought about him long enough. And as for bonus points, killing him doesn't even work, as his powers just split into separate beings. So yeah, he's quite the mysterious Eldritch Abomination.