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Psycho Knife Nut

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"A little bit o' pain never 'urt anybody... if you know what I mean. Also, I think knives are a good idea. Big, 'fuck-off' shiny ones. Ones that look like they could skin a crocodile. Knives are good, because they don't make any noise, and the less noise they make, the more likely we are to use 'em. Shit 'em right up. Makes it look like we're serious. Guns for show, knives for a pro."

Knives have a long history in media of being the weapon of choice for slasher villains, unhinged individuals, or anyone with a penchant for violence.

One reason for this is that knives are scary, as a single glimmer from its profile in Ax-Crazy hands has been known to provoke screeches of horror (that and the possibility that they're more painful than any gunshot will ever be). Another reason is that knives are very accessible — if a once-sane person suffers from Sanity Slippage, chances are they already have a kitchen full of sharp knives with which to get their killing spree started once their mental state reaches "murderous". Knives are also relatively easy to deal damage with, and a great way to release pent-up rage and hatred. Once a crazy knife-wielder gets close enough to enter a stabbing frenzy, it's almost impossible for their victim or those close by to stop them.

Many knife nuts do the Five-Finger Fillet to showcase their dexterity and general disregard for safety.

A lot of them may double as blade enthusiasts.

Sub-Trope of Weapon-Based Characterization. Related to Devious Daggers, Sinister Switchblade, Sinister Shiv, Machete Mayhem, Kukris Are Kool, and Bayonet Ya. No relation to Gun Nut despite the similar names.


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    Anime & Manga 
  • Cowboy Bebop:
    • Udai Taxim from "Black Dog Serenade" is a dangerous convict who likes to use knives.
    • Preference for katanas aside, Vicious throws a knife into Spike's shoulder in their final match. He also uses a combat knife to literally Stab the Scorpion and thus gain Gren's trust. While he's perfectly capable of handling guns, his use of blades in his later years reflects his more openly Ax-Crazy behavior.
  • In Digimon Ghost Game, the Cyber Ninja Digimon Serial Killer Sealsdramon exclusively attacks using its special attack "Death Behind", which is a thrown combat knife powerful enough to One-Hit Kill even other Champion-level Digimon.
  • Durarara!!: Haruna Niekawa, while possessed by Saika, uses a knife to stab people with in order to spread Saika's "children" before she snaps out of it.
  • Fullmetal Alchemist:Barry the Chopper likes to cut up helpless people for fun, so he carries a giant meat cleaver and a couple of carving knives to help with the process.
  • Kuro(u)do(u) Akabane (a.k.a. Dr. Jackal) from Get Backers pulls off Diagonal Cuts in rapid succession with his (wait for it) scalpels, when he's not throwing them en masse ("Deadly Rain!"). And you don't want to know where he stores them...
  • The Nightmare Fetishist narrator in Goth becomes one of these over the course of the series. He gets his first set of knives from a collection left behind in a home that a Serial Killer had abandoned and quickly becomes proficient with them, his own homicidal urges being a strong source of motivation.
  • Asakura Ryouko, the Girl with Psycho Weapon in Haruhi Suzumiya. Worse yet, it's a combat knife with nasty spikes on the backside. And Asakura can be scary. Very scary.
  • My Hero Academia:
    • Stain, the Hero Killer, is a crazed Knight Templar on a mission to wipe out all heroes he deems "unworthy". Although his Katana is his main weapon, he also carries several knives, including five daggers and some throwing knives, which he uses to draw his enemies' blood as his Quirk paralyzes whoever's blood he ingests.
    • Himiko Toga is an Ax-Crazy Yandere who carries multiple knives on her as her weapons of choice. She derives great pleasure from stabbing those she loves with them.
  • Re:Zero: Elsa Grandhirte is an Ax-Crazy assassin who fights with kukri blades.
  • Reborn! (2004): Belphegor is a knife-wielding psychopathic assassin in the Varia. He wields hundreds of knives at a time by stringing them along with Razor Floss.
  • Record of Ragnarok: Jack the Ripper is a Serial Killer who uses a nigh limitless number of knives in his fight against Heracles. Even his Start of Darkness involved murdering his parents with a knife.
  • Tokyo Ghoul: Both Suzuya and eventually Mutsuki fit the bill, having several knives which they use with frightening skill and enjoyment.

    Comic Books 

    Fan Works 
  • A Certain Droll Hivemind: Abe Eiko, it turns out, was a Dark Side assassin who liked using knives. She managed to get herself benched by flubbing a mission, but she's still very fond of her knives. She admits she's trained in guns, but prefers her knives because "the rush is so much better, you know?"
    She smiled at me. Her smile was lopsided - the right side of her mouth turned up more than the left side. I flinched when suddenly a knife appeared in each hand. They were thin blades considerably more narrow and pointed than a standard combat knife. They were also made of swirling black and white indicating that they were made via her esper power.
    She held them like she was familiar with their use. The Network was alarmed, but also pleased that we had predicted the threat posed by Abe Eiko correctly.
  • In Coveralls, Scully acts a lot more unhinged than normal and has a "knife office".
  • A Moth to a Flame, Marcy was given a Laser Blade knife by Andrias and during her Villainous Breakdown stabs Sasha in the leg with it with a Slasher Smile.
  • In Old West, two of the antagonists, Ramirez Arvenga and Kepper, fight with knives. The former is fond of using his knife in collecting Creepy Souvenirs, while the latter is unhinged and carries with him every kind of knife imaginable. He's even known by the trope name.

    Films — Live-Action 
  • Barbarella: The insane Black Queen of Sogo wields two double-bladed knives quite adeptly, and she drives them through Barbarella's attackers.
  • The Dark Knight: The Joker carries a number of knives on him. He states that they're his preferred weapon because he can savor his victims' subtle changes in expression as they die. He even carries a potato peeler.
  • Dick Tracy, Detective: Splitface hacks his victims to death with a surgeon's knife stolen from an undertaker.
  • Die Hard with a Vengeance has Katya, and to make clear she's very psycho, as the baddies invade the federal reserve, she repeatedly slashes a guard until Simon holds her back saying "I think he's dead, my dear."
  • Dune: Part Two: This is one of Feyd-Rautha Harkonnen's defining character traits. In his Establishing Character Moment, he gets presented a set of knives by a servant which he proceeds to test out by killing two of the handmaidens attending him, ends up Licking the Blade of one of the knives, and berates and punishes the servant as he deems the knives are not sharp enough for his tastes. He is also shown to be a Sadist who takes great pleasure in torturing some of the Atreides captives before having them drugged to fight him in the arena as part of his coming of age celebrations.
  • Dust Devil: It's the Dust Devil's weapon of choice when he cuts up his victims.
  • The Elf: The elf doll is seen with a knife in its hand for most of its scenes. When it attacks people, it sometimes uses it.
  • Halloween: While Michael Myers is known to murder his victims with anything he can find, or with his bare hands, his most iconic weapon is a pointy kitchen knife. He's also a complete sociopath who shows no emotions or empathy; all he lives for is murder, murder, and murder.
  • The Hobbit: The Desolation of Smaug: When the Company is taken into custody by the Mirkwood elves and searched for weapons, Fili is shown to be carrying an improbable number of knives concealed on his person.
  • The Locals: homicidal farmer Bill favours the knife, and all of his kills are made with one.
  • In Masquerade (2021), Rose stabs Daniel repeatedly with a kitchen knife, and there are several lengthy shots of the leather-clad intruder holding the blood-smeared weapon just to emphasize how crazy this woman is. Subverted with the reveal that Rose is doing this out of revenge for Daniel killing her parents.
  • The New York Ripper eviscerates his victims with a variety of knives.
  • Nightbreed: The serial killer Dr. Decker prefers to use huge carving blades to kill his victims, often appearing with one in each hand. He's briefly seen in his apartment with an entire collection of knives and blades laid out in front of him on a conference-style table.
  • Psycho: In the scary category, the shower scene of Alfred Hitchcock's masterpiece involves a screaming woman, a big knife, and scary music.
  • Razors: The Return of Jack the Ripper: Jack the Ripper uses a box set of knives, each of which has a special meaning to him. The knives are so much a part of him that they constitute an Evil Weapon and allow his spirit to return to Earth.
  • Repo! The Genetic Opera:
    • Luigi Largo. He's known to have sex with the stab wounds he's inflicted, among other delightful things. The Repo Man himself, though his "companion" technically makes him a Scalpel Nut.
  • Ripper: Letter from Hell: The killer wields a large butcher's knife.
  • Scream: Every killer that takes the mantle of Ghostface. Has almost always used a rather unique Buck 120 hunting knife, although how they appear usually changes quite a bit. An interesting fact about the Buck 120 is that it was seen on the film posters of Friday the 13th 4, 7 and 8. The knife's appearance on these iconic horror film posters may be why it was chosen as Ghostface's primary weapon.
  • Sha Po Lang:
    • Jack, the psychotic Triad assassin played by Wu Jing, does most of his killings with his tanto knife.
    • Ah Zai, the evil browless assassin from the sequel, does knives as well. His weapons of choice are folding knives that he uses both for melee and for throwing. He ultimately faces down Chan Chi-Kit, who is played by Wu Jing, in a furious duel that is reminiscent of Jack's final battle with Ma Kwun from the first movie.
  • Special Female Force: The Dragon Lung is a deranged Sadist that favors using a wicked-looking serrated knife as his weapon. Right in his first scene in the Action Prologue, he's seen practicing his skills by scattering a box of cockroaches all over the road he's sitting on, and then using his knife to skewer roaches. Later his Hand Stomp method on the heroine who's Hanging by the Fingers is to gleefully drive his knife underneath her fingernails, slowly tormenting her until the pain gives away, causing her to fall to her death.
  • Suspect Zero: Serial Killer O'Ryan uses a long, curved dagger, both for killing his victims and his signature of removing their eyelids.
  • Sockbaby: Though initially he might seem to be a wacky ninny, Davis The Grey is still deadly with a switchblade. He uses one to murder Burger in the car and steal Sock Baby while Ronny is distracted, and very nearly defeats Ronny with it.

  • Angels of Music: Rollo is the knife-thrower in Le Théâtre du Grand-Guignol in "Guignol" who is dismissed for collaborating a little too willingly with the horrors. He returns in "Deluge" equipped with dozens of blades and looking to exact vengeance on the Angels by skinning them.
  • Discworld:
    • Jonathan Teatime is a knife-wielding, psychopathic assassin in Hogfather.
    • Carcer Dun is a knife-wielding, psychopathic Serial Killer who always has an extra one.
    • Pteppic is a certified assassin and Pharaoh of Djelibebyi. When he finds out that his "companion" feels naked without her many bracelets, he has to admit that he feels naked without his knives.
  • In the Fingerprints series, one villain says the memorable lines, "I wonder how many cuts it will take you to die? I bet thousands and thousands..."
  • The original novel version of Goth has several of these.
    • The café owner uses a case of knives to carry out his murders. After deducing the café owner's identity, Itsuki takes the knives for himself. He later lends one knife to a little girl so that she can kill her abusive stepfather with it.
    • Mr. Shinohara uses a meat cleaver to cut off the hands of his victims.
  • Clove from The Hunger Games has many knives and is very skilled at throwing them. She is also quite sadistic, what with trying to torture Katniss to death and all.
  • Bèbelle from Malevil. A Creepy Crossdresser who pretends to be a woman to get close enough to cut throats.
  • New York to Dallas has Isaac McQueen, a pedophile and murderer who "favors knives as weapons and as a means of intimidation".
  • Sonia Steiglitz, the beautiful and sadistic daughter of the ex-CIA chief/archaeologist villain of The Takers, a modern Two-Fisted Tales homage by Jerry Ahern. She uses guns when necessary, but prefers a knife.
  • The Wheel of Time: The Merger of Souls between Padan Fain and Mordeth makes them even more unhinged and malevolent than their component parts, and they wield a cursed dagger from Mordeth's home city that they think of as a part of themselves. Whereas the dagger can reduce anyone else to a mess of putrefaction with a scratch, Fain takes up Licking the Blade.
  • The Witch of Knightcharm: The witch Chosovi is introduced while sharpening knives, and when an annoying rookie keeps bothering her, Chosovi very quickly starts joking about stabbing her.
  • Worm: While the mass murdering supervillain Jack Slash can use just about any blade as a conduit to project their cutting edge invisibly, he most often uses knives and razors.

    Live Action TV 
  • Batwoman (2019). The balisong is the weapon of choice for mad supervillain Alice, who lampshades the advantage of being able to flip it around in a menacing fashion while explaining your Evil Plan.
  • Dollhouse has Alpha, who really shows a love for slashing and cutting people during his more psychotic personality periods. He was already a psychopath before the mass upload and it just got worse.
  • Forever:
    • In the pilot, when Henry's colleagues generally agree that he's highly creepy, the fact that he uses a large hunting knife as one of his main autopsy tools doubtless helps contribute to this image.
    • In both "Hitler On the Half-Shell" and "The Last Death of Henry Morgan" Henry has had bodies on his autopsy table of people Adam tortured to death as part of his quest to reacquire the pugio knife used in his first death, which was taken from him by the Nazis at Auschwitz. They were covered with long, straight wounds consistent with a knife, and Henry remarks, even before knowing who caused them, that they are the mark of a true sadist who was enjoying the torture. Adam has also used the knife on himself for the Mundane Utility of slitting his own throat simply to get out of a location unseen, thanks to his Resurrection Teleportation.

  • Rob Cantor's "Shia LaBeouf" portrays Shia LaBeouf as a hermit murderer who goes after his victims with a knife and eats the bodies.
  • Jim Croce:
    • Based on what Slim does to Big Jim in "You Don't Mess Around With Jim", he likely qualifies. To clarify, "And when the cuttin' was done the only part that wasn't bloody was the soles of the big man's feet. Yeah, he was cut in about a hundred places..."
    • The guy "Bad, Bad Leroy Brown" tangles with at the end:
      Well, the two men took to fighting
      And when they pulled them from the floor
      Leroy looked like a jigsaw puzzle
      With a couple of pieces gone

    Mythology and Religion 
  • The Malingee of Yolngu lore is a creature that stalks people at night to stab them with a knife. You can tell it is coming thanks to its rattling knees, but it is usually too late.


  • Dead Ringers: Brian Perkins, gangland boss of BBC Radio 4, has a large knife he likes to use on those who incur his displeasure. He also occasionally uses it to help people in non-deadly ways, like opening lunchboxes. While calmly recounting his murder victims screaming like "stuck pigs".

    Tabletop Games 
  • Warhammer 40,000
    • Konrad Curze (Basically Batman as a Knight Templar Serial Killer) uses throwing knives rather than a gun. On the tabletop, they are the one of the few weapons in the game that can potentially circumvent Invulnerable saves altogether.
    • The Dark Eldar gladiator Lelith prefers dual-wielding knives in combat. In-game, the 8th Edition rules for Lelith's knives grant her extra attacks and are able to cut through all but the thickest armour.
    • In the Kill-Team spinoff game, the Chaos Legionaries team has the "Shrivetalon", whose primary weapon, Flensing Blades, are portrayed as paired knives on the Kill-Team upgrade sprue. On the battlefield, Shrivetalons have the ability to place a token representing a grisly, mutilated corpse to intimidate enemies, and can drain AP from nearby enemies by gruesomely killing people in melee. The general vibe is that of a Serial Killer who just so happens to be a Super-Soldier in Powered Armour.

  • After she is rescued from the Wolf, Little Red Riding Hood in Into the Woods is rarely if ever seen without her knife. It's implied that she becomes rather obsessed with hunting down wolves for her fur cloak, with which she replaces her red cloak (taken by the Baker).
  • The Mrs. Hawking play series: Mrs. Hawking's preferred weapons are knives of all kinds, from a thin, sharp letter blade to throwing knives to a plain sturdy Bowie.
  • Sweeney Todd: The Demon Barber of Fleet Street: Sweeney Todd's weapon of choice is the straight razor. Between him and Jack the Ripper, the razor soon developed a reputation as a murder weapon.
  • The Three Penny Opera by Kurt Weill and Bertolt Brecht is probably best remembered for its Villain Protagonist Macheath, or, as he's referred to by the song about him, Mack der Messer. Or in English, Mack the Knife, which is well known from the swinging version recorded by crooner Bobby Darin. Although by the events of the musical Macheath is actually nuts coasting on his reputation, he clearly had a period where he earned that reputation and this trope applies.

    Theme Parks 
  • Universal's Halloween Horror Nights: As you might expect from such a classic horror weapon, scareactors wielding these have shown up quite a bit over the years, including horror icons like Michael Myers and Norman Bates.

    Video Games 
  • Assassin's Creed Syndicate: Jack The Ripper is perhaps the most exaggerated version of the killer so far. Of course, he mostly wields a knife and a blade in general. However while the real killer mostly struck at night (or at least early morning hours), this version massacred in broad daylight. Also during the DLC, there were plenty of witnesses to Jack's bloody crimes, while the real Ripper was as elusive as a ghost.
  • The Black Heart: Peketo has an infinite supply of knives that he uses in combat. Keep in mind that he murdered seven people for the sake of a color while he was still a preteen.
  • In Cultist Simulator, knives are a common symbol of Edge, the aspect of struggle and strife. Particularly the case for one Edge-aspect cultist, Elridge, "an elegant man of inelegant habits". He becomes better at hiding the tools of his hobbies and other telltale signs thereof as he progresses within the cult, but at first:
    He has almost learnt not to pick his teeth with his knife. He has not yet learnt to keep his knife in his boot.
  • Crush Crush: Ayano repeatedly tries to Murder the Hypotenuses with knives and cleavers, although she does use other methods like Tampering with Food and Drink.
    Ayano: [describing her new knife] Guaranteed not to slip, even when covered in... milk.
Like with Pamu:
Pamu: Wow! Some broad has been stalking me with a knife! She's so disturbed and adorable — I love her!
Ayano: I think that Pamu might not be human... She laughs when she's stabbed... I hear.
And Alpha:
Alpha: My handlers told me that I received some poisoned chocolates.note  I wonder if by accident?
Alpha: I think someone tried to hack my servers today. And by "hack" I mean with a meat cleaver.
And Quill:
Quill: Are Cat-Catchers allowed to use steak knives for their jobs? Because the one that's chasing me sure is.
And regarding Elle:
Ayano: I heard people with narcolepsy sometimes slip and fall and stab themselves with knives 20 or 30 times. How awful!
  • Many of the Killers in Dead by Daylight wield knives. Some are famous and iconic Guest Fighters from horror movies, such as Michael Myers and the Ghost Face, others are original characters such as the Legion and the Trickster. All are Ax-Crazy murderers whose goal is to kill every player on the Survivor team.
  • Although Lucas Kane in Fahrenheit never uses a knife outside the opening sequence, he is depicted holding a bloody blade on every box art to underline the psychosis surrounding him throughout the game.
  • Fallen London has Serial Killer Jack-of-Smiles, an Expy of Jack The Ripper. Actually, Jack-of-Smiles is his knives, which explains his plentiful bodies to use. The knives are alive, have a mind of their own, and will take over yours if you hold one for too long.
  • Fatal Fury: The Psycho for Hire Ryuji Yamazaki habitually keeps a switchblade in his pocket. And he's not above shanking his foes with it while laughing his head off.
  • In The Legend of Zelda: Skyward Sword, Ghirahim is a vicious fighter who can summon an endless supply of daggers in his boss fights to use in conjunction with his sword.
  • Like a Dragon: One of Majima's signature weapons next to a baseball bat is a tanto dagger he keeps on him at all times. Once that comes out, you learn right away why he's called the Mad Dog of Shimano.
  • Master Detective Archives: Rain Code: Later in the game, we are introduced to Professional Killer Fink the Slaughter Artist, a local assassin-for-hire in Kanai Ward whose signature weapon is a knife with an F engraved on the hilt. The plot of Chapter 4 revolves around his supposed infiltration of Amaterasu's research lab. He did infiltrate it, and he promptly attacks Yakou with his knife (as part of Yakou's overarching murder plot), but the "psycho" part doesn't apply, as in this situation, he was actually attacking Yakou due to being hired to do so. In general terms, though, Fink is most definitely psycho about his use of knives as a weapon.
  • Mystery Case Files: Broken Hour introduces Meredith Huxley, a psychopathic woman who murders people with an ornate dagger.
  • OMORI: Both Omori and Sunny use knives as their primary weapons. Add this to the way Omori looks when Manic, and it's no surprise that much of the fandom sees him this way.
  • Pathfinder: Kingmaker: Nok-Nok is a Heroic Comedic Sociopath goblin who dual-wields kukri as his main weapons. While he believes the Player Character is his wise Mentor Archetype who will turn him into a True Hero and thus never harms you or your companions, Nok-Nok will offer to "ssstab" practically everyone else you meet who cheeses you off.
  • One of the many signifiers that Pavia of Reverse: 1999 is the Crew's Token Evil Teammate is the maniacal glee Pavia has when using his knife to carve up his enemies.
    Pavia: Police's number? I'll carve it on your face!
  • The Super Spy has a mentally-unhinged terrorist assassin called "Geese" who fights with his knife, despite most other bosses using firearms. You first confront him in a conference room, where he's gleefully threatening a hostage with his knife, and the entire boss battle takes place in a badly-vandalized room sliced apart by Geese.
  • The original Time Crisis has the Big Bad, Sherudo Garo, who's an expert in throwing knives and in his introductory cutscene, happily taunting the kidnapped Rachel McPherson by holding his knife on her face, giggling all the way.
  • Undertale: The final and most powerful weapon in the game is the Worn Dagger, but on the Genocide Route it becomes the vastly more powerful Real Knife (as opposed to the Toy Knife). Given that it presumably belonged to the First Fallen Human, and said human was stated as sometimes making a "creepy face" and described as "not the greatest person," it's possible that they qualified as this. Given that by the end of the Genocide Route, both the player character and the First Fallen have gone utterly insane, they probably both qualify as this even if they didn't before. Obviously, it's made a lot less ambiguous in most fan works.
  • Madotsuki from Yume Nikki is frequently depicted as one because of a widespread Player Tic which involves killing everyone, with the knife being the only weapon available.

    Visual Novels 

    Web Animation 

  • 8-Bit Theater: The violently unstable, Hadoken-happy Black Mage keeps a dagger around in case he runs out of spells... or feels like using it on one of his "teammates".
  • Basic Instructions: The Knifeketeer is an Anti-Hero version. He is about the only superhero to actually fight crime, and does have a non-lethal knife that's a boxing glove on a very short stick, but is generally treated like a dangerous lunatic by allies and enemies alike. His sidekick, Stabby, is even worse; it's heavily implied that the crudely drawn S on his costume is a Creepy Souvenir from murdering both of his parents.
    The Judger: Knifeketeer, I know you've always wanted to stab Omnipresent Man. What do you say in your defense?
    The Knifeketeer: I've always wanted to stab everyone. I just love to stab.
    The Judger: Do you even know what the word "defense" means?
    The Knifeketeer: It's a kind of stabbing, right?
  • Girl Genius: DuPree is ecstatic about getting to kill and torture and her implements of choice for both are the many little knives she keeps on her person at all times.
  • The Guy Upstairs: Adam’s preferred weapon of choice is a knife, which he uses to kill the woman in episode 3 via slashed throat and repeated stabbings.
  • Homestuck: Ax-Crazy Jack Noir absolutely loves his knives, and has a habit of stabbing people with said knives. If he ever gets a chance to stab something, expect him to do it, even as a greeting.
  • Lone: Mostly Played for Laughs with Lone's mother in a flashback. If somebody is actually threatening her daughter, she doesn't need a knife to make them stop.
  • The Order of the Stick: Heroic Comedic Sociopath Belkar Bitterleaf dual-wields daggers. While capable of holding the Sanity Ball on occasion (though he's probably the second-least likely to do so after Elan), Belkar is extremely violent and mostly kept in line by the rest of the gang threatening him with retributive violence if he steps out of line.
  • From String Theory, we have Professor Phineas Armastus, the resident psychopathic murderer of Nevada State Penientiary, who can clear a room of guards armed with automatic rifles in a matter of seconds with nothing but a pair of prison shanks. And then take their gummy bears.

    Web Videos 
  • Part of Ryan Haywood's Token Evil Teammate shtick in Achievement Hunter videos is that he loves knives and his first objective in games is to murder. He also keeps a cup filled with them at his desk.
    Ryan: Why do I need a cup full of 37 knives? I don't, but I like it!
  • Evan of Everyman HYBRID is an absolute fiend for knives, switchblades, cleavers, daggers, and knife gloves a la Freddy Krueger. He's rarely seen without some kind of cutlery in his hand, which is getting increasingly worrisome, as he seems to be on a greased slide to Ax Craziness. Oh, and he's occasionally possessed by a disembodied homicidal maniac.
  • Rats SMP: In spite of being designated as the Safety Rat, Jimmy is decidedly one of the more… unhinged rats, shall we say, and has been constantly running around with a knife since Day 1 and threatening humans every other day, and is the only rat with a non-rat body count. He is also the only rat who endorses Scott's Revenge Before Reason plan against the cats on Day 47 when he first hears of it, though his opinion immediately shifts to opposition when it's clear it's not working as intended.

    Western Animation 
  • Roberto, a mentally unstable robot from Futurama, has an obsession with stabbing things with his trusty "Stabbing Knife".


Video Example(s):

Alternative Title(s): Psychotic Knife Wielder



While exiled to Yoyleland, Leafy undergoes severe insanity, to the point that if anybody provokes her, she'll assault them with a barrage of knives.

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Example of:

Main / PsychoKnifeNut

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