Fear is all in the eye of the beholder, and in part, this is what makes horror so divisive. There are certainly those who don't care for scary content of any stripe, but even horror devotees have strong opinions on what constitutes a "good" scare.
Anime is no stranger to horrifying its audiences, and the body-horror sensibilities and alienation that take center stage in many anime are almost universally effective. Few monsters have become so notorious worldwide as titans, often mindless but sometimes all too aware of their actions. Enormous, nude, and relentless, the titans are unsettling zombies that are all too close to being human beings. While Attack on Titan has cornered several anime markets, the series is far from the only anime to present deeply upsetting monsters.
9 Envy's Second Form Is A Thing of Nightmares (Fullmetal Alchemist: Brotherhood)
When Ed and Ling Yao are trapped in the depths of Gluttony's stomach along with Envy, arguably the most interesting of the deadly homunculi, the three have little choice but to form a brief alliance. Envy is far from stupid and proves one of the most tenacious of their siblings, and Ed and Ling certainly aren't going down without a fight. But when Envy reveals their second form in the depths, it proves more disturbing than either Ed or the audience anticipated.
Like the other homunculi, Envy harbors a philosopher's stone at their core. Unlike their siblings, the human souls used to create that stone protrude from Envy's body, screaming and weeping, forever trapped in their flesh. In a show that rarely pulls punches, this aspect of Envy still feels especially sickening.
8 The Shinigami Imply Darkness Watches Over The World (Death Note)
Sure, Ryuk and company are an ugly bunch. As gods of death, that's to be expected, and yet it's far from the sole aspect that makes the various shinigami of Death Note so disconcerting. Ryuk is most frightening not when he accompanies Light like a toxic hidden shadow, but when the audience catches brief glimpses into the world the shinigami have long inhabited.
People speak of angels watching over them, but Ryuk and the other shinigami are far from angels, and they don't live in any kind of heaven. The shinigami realm is bleak and desolate, devoid of color or life, the grandstand where shinigami watch over humanity like bored spectators, taking small joy from mankind's endless failures.
7 Lil' Slugger Is a Haunting Poltergeist (Paranoia Agent)
Poltergeists are usually seen as a bit more playful than other ghosts, often conjured up by the repressed feelings of humans in the vicinity. But Lil' Slugger of Satoshi Kon's Paranoia Agent is altogether more sinister than most Hollywood poltergeists.
Rather than switching on televisions or stacking chairs, this phantom skates around the city of Musashino beating people seemingly at random with his bat. Lil' Slugger is an urban legend brought to life, and it proves almost impossible to defeat a creature who exists merely because society willed him to, powered by their belief in him.
6 Angels Are Disconcerting At Best (Evangelion)
The angels of Evangelion are as inexplicable as their designs are. They arrive in various forms, intent upon destruction, sometimes humanoid and other times barely geometric. While the angels are given a reason for attacking earth by the end of the series, for the bulk of the anime they are incomprehensible monsters intent on destruction.
The angel Ramiel is something of a joke in the fandom: a floating diamond that seems more like the result of budget cuts than creative design. But the idea that the angels can look like absolutely anything grants them a profound degree of ominous power. All that infinite possibility means some of the angels are much closer to being human than anyone would like, and even live and breathe among the main cast of characters.
5 Mushi Are Mindless Yet Sinister (Mushishi)
Mushi are beings that exist somewhere between spirits and parasites, and the mushi master Ginko of Mushishi travels the land exorcising them from the humans they infect. Mushi, like fungi, are not intentionally monstrous – they infect their hosts without malevolent intent. Still, sometimes the parasitic nature of these mostly-unseen species proves deeply unnerving.
Silvery fish that blind those who look upon them, shadowy snakes that burrow into the ears and devour memories, butterflies that feed on the life force of small animals, centipedes that eat eyeballs: these and many more mushi feature in the series, haunting the audience forever thereafter.
4 The God Hand Made A True Monster of Griffith (Berserk)
Griffith was always a complex character, but he wasn't always an absolute monster. His wit and ruthlessness are initially traits that endeared him to early readers and watchers of Berserk, and his ability to match Guts in battle made him a formidable frenemy. But Griffith goes from a brilliant tactician to a wounded man who's willing to do quite literally anything to gain power. When Griffith makes the decision to sacrifice his men and assault Casca in order to join the God Hand, he becomes irredeemable.
The culmination of Griffith's ambitions is as horrifying as it is effective. A once likable character becomes despicable in an instant. And while the story would likely be written differently today – female characters should not be treated this way for the sake of shock value – there's no question that the transformation is unforgettable.
3 Serial Killers Are All Too Real (Monster)
The titans were all once people, but most have forgotten themselves entirely. Yet in the case of several characters, the titans are cognizant of their actions. Titans become more frightening when they move with purpose, revealing that they know what they're doing. In Monster, the central villain knows precisely what he's doing.
Urasawa places the audience and protagonist in an impossible situation: Johan was once a little boy, and he deserved to be saved as all children do. But what happens when a child saved from death turns into a sociopath who kills countless people thereafter? Where is the line drawn between a good deed and a mistake? The grays in Monster are impossible to ignore, and thinking too much about this story has kept viewers awake for years.
2 The Parasites Would Give John Carpenter Pause (Parasyte: The Maxim)
Body horror isn't to every viewer's taste, but the trope is incredibly prevalent in anime. And while cult pulp films have often indulged in twisting and bending the human body in impossible, unsettling ways, few anime have achieved the pure 80s John Carpenter horror vibes like Parasyte: The Maxim.
Monsters are scary enough when they exist outside of us, but Parasyte internalizes that fear, taking it one step further by placing the monsters within us. A character can't run from something that quite literally lives inside them. And what happens when a character becomes more sympathetic to the monster than the human beings surrounding him?
1 Junji Ito's Creations Remain Untouchable Horror Icons
While Junji Ito Collection disappointed many fans of the author, there's no doubt the works that inspired them retain legendary status even beyond the anime community. Uzumaki and Gyo have horrified readers for decades now, and there are few mangaka who can elicit true fear with a mere sketch in the same way Junji Ito can.
Next year the world will be treated to an animated remake of Uzumaki, and the Adult Swim trailer alone promises the experience will be something else. Ito excels at twisting the mundane, at transforming everything from spiral patterns to cats into sinister symbols. There's no escaping the monsters Ito presents because they are all around us.