Instrument of Murder



"Mexican Bandito: Tell me, Kabong, what do you use? A sword? A whip? A shillelagh? El Kabong: I use a gee-tar! Kabong! (kabongs bandito)"

- Quick Draw McGraw

So you're an assassin who is also a musician. Unfortunately you're not a Musical Assassin and cannot kill people with the power of your music alone. So what are going to do? Why, have a musical instrument that doubles as a deadly weapon of course. A step up from Senseless Violins, with no danger of your weapon being discovered if anyone opens your case.

This trope covers weapons hidden in musical instruments. For assassins who kill their targets with music, see Musical Assassin. For weapons used as instruments, see Instrumental Weapon.

Anime & Manga

 * Midvalley the Hornfreak in Trigun is mostly a Musical Assassin who tears it up with sound waves from his saxophone, but it's also a complicated firearm that he eventually
 * The chancellor of Alabasta in One Piece also used a firearm/saxophone as his weapon of choice.
 * M.M. in Katekyo Hitman Reborn uses vibrations from her clarinet to microwave and melt things. In a pinch, she can also hit people with it.
 * Haruko from FLCL wields a pull-string-ignition bass guitar. It can also blast doors in half with some kind of firearm function. It's more a question of what Haruko can't do with her guitar.
 * Genkaku the Hypermonk from Deadman Wonderland has a guitar that can split into a pair of machine guns. Or, alternately, it turns into a gun capable of punching head-sized holes through people. Take your pick.
 * Scrapped Princess has the Silencer, an assassin who can summon and control deadly insects with an instrument.
 * In Saint Seiya, the Asgardian God Warrior Benetnasch Eta Mime, wears a Cloth reminiscent of a harp. As such, he is prone to laying down Razor Floss around the environment as traps, as well as send them flying towards his opponents to entangle them. Note that his harp's strings are strong, and sharp enough, to crack and cut through solid rock, as well as Bronze Cloths and the very human skin of the Saints wearing them.
 * A normal sized violin in Violinist of Hameln: Shchelkunchik.
 * Sailor Neptune's final attack in the manga version of Sailor Moon, Submarine Violon Tide, is - you guessed it - an attack using her violin. She also whips it out earlier on in the Infinity Arc and incapacitates the Inner Senshi. Sailor Mercury, meanwhile, uses a watery lyre for her final attack, Mercury Aqua Rhapsody.
 * Samurai Champloo: In the first part 'Hellhounds for Hire' Jin is disguised as a woman carrying a biwa (a traditional Japanese instrument similar to a guitar). When asked to play a song on it, he pulls his katana from the neck, and reveals that he is actually a samurai. He also happened to have smoke bombs hidden in the body of the instrument.
 * Shattered Angels has one of these in the form of the Mana Buster, a modified cello that provides fire support during the final showdown.
 * Gintama: The character Kawakami Bansai can use the strings from his shamisen to restrain people.
 * The Tokyo Mew Mew girls have a habit of using these. Mew Lettuce has a pair of castanets, though at least she shoots water from them, and Mew Pudding has tambourines can that rend the earth and encase a target in jello.
 * Cure Lemonade from Yes! Pretty Cure 5 also uses castanets, which is odd, because her teammate, Cure Mint, is an Expy of Mew Lettuce. Also from the Pretty Cure series we have the Pine Flute, the Passion Harp, the the Shiny Tambourine, and the Love Guitar Rod.
 * Haji from Blood Plus borders on this trope. He regularly uses his cello case as a weapon/shield. The cello itself is only used to perform music. One does have to wonder how it hasn't been smashed to pieces inside his case though.
 * Fullmetal Alchemist: Catherine Armstrong uses a piano to attack Yoki when he tries to steal money from the Armstrong family. Given her Super Strength, That Has Been Passed Down Through The Armstrong Family For Generations.
 * Blade of the Immortal: The ridiculously skilled Makie Otono-Tachibana, who specializes in Waif Fu, wields a double bladed three-section-staff called Haru-no-Okina concealed in a hollowed-out shamisen, a mandolin-like Japanese instrument which she is able to play when not slicing and dicing her enemies.

Comic Books

 * In The DCU, golden age Green Lantern foe named the Harlequin had a weighted mandolin that served as a club (and a vaulting pole!).
 * Also in The DCU, the Fiddler, a golden age foe of The Flash, was primarily a Musical Assassin. However, he would occasionally use gimmicked violins containing blades or guns.
 * The preferred weapon of Minstrel Maverick, a Western character from DC Comics, was a reinforced guitar that he used to whack owlhoots.
 * One Justice Society of America foe (from All Star Comics #38) masqueraded as Nero and carried a fiddle that spewed strangling gas.
 * Spy vs. Spy sometimes has weapons disguised as instruments.
 * In Nextwave, Elsa Bloodstone one time was knocked into a store fighting brocolli men, grabs a guitar, and dispatches several.
 * Brazil once had a superhero, Golden Guitar, who used a gizmo-filled electric guitar to fight crime.
 * While doing a Jack Benny homage, The Joker used a violin bow with a razor blade instead of a string.
 * Bullseye has killed people with a piano key, a clarinet reed, a spit valve and a french horn.
 * One-shot Batman villain the Maestro (Batman #149) used a number of gimmicked instruments, including a harp that shot arrows and horns that fired bullets.
 * Although seldom used as a weapon in the comic, Captain Clarinet's clarient from PS238 does possess a number of combat functions.
 * In the Marvel Universe, Dazzler had a foe called Johnny Guitar who wielded an electric guitar that fired sonic blasts. He had a partner in Dr. Sax, and you can probably figure out the rest on your own.
 * The Minstrel, one-time foe of Doll Man, who wielded a flame-throwing banjo.

Film
"Bond: "I guess we all have to pay the piper sometimes." Q: "Oh, pipe down 007!""
 * In the movie The Forbidden Kingdom, Golden Sparrow has throwing blades disguised as the tuning pegs of her pipa.
 * The World Is Not Enough had a bagpipe flamethrower being tested in Q's lab.

"Q: "Something we're making for the Americans. It's called a Ghetto Blaster!""
 * Q has made a couple Instruments of Murder over the years. The Living Daylights featured a boom box with a built-in rocket launcher.


 * The Pink Panther Strikes Again. An assassin uses a blowpipe disguised as a clarinet (or possibly uses a clarinet as a blowpipe, the movie isn't clear).
 * The Mariachi from Once Upon a Time In Mexico used a guitar that doubled as an assault rifle and grenade launcher in the opening shootout/flashback. The narrator freely admits that the details have been... embellished. The character himself doesn't actually have one, instead using the old "guns concealed in a guitar case" trick.
 * One of his friends does have a guitar that doubles as a flamethrower.
 * Matt Helm movie The Ambushers. An assassin tries to kill Matt with maracas that have built-in guns.
 * Amongst the weirdness in Wild Zero are katanas hidden in the necks of the band Guitar Wolf's guitars, and guitar picks thrown like shuriken.
 * In Our Man Flint, Galaxy agent Gila uses one of the strings on a harp as a bow to launch a poisoned dart.
 * In Disney's animated Robin Hood Alan-a-Dale and Friar Tuck use Alan's lute as a makeshift bow to shoot down the high flying Sir Hiss.
 * At the climax of Rock and Rule Omar uses his curiously-shaped, futuristic guitar as an axe to severe the power cables of Mok's machine
 * In Casino Royale 1967, Ursula Andress uses the old machine-gun-in-the-bagpipes trick.
 * The Fastest Guitar Alive, a humorous Western from 1967, stars Roy Orbison (!) who wields a guitar/rifle.
 * The Harpists from Kung Fu Hustle, who could summon flying swords and ghost pirates from their guqin. They might overlap with Musical Assassin but they didn't seem to be able to use their powers without the instrument.
 * Zombieland. Tallahassee bludgeons a zombie with a banjo.
 * In another scene, a nun drops a piano on a zombie.
 * Banjo in the western Sabata hides a repeater rifle inside his, well, banjo.
 * The killer in Slumber Party Massacre II film uses an electric guitar infused with a power drill.
 * The seventh Friday the 13th has Jason kill a girl by jamming a novelty party horn into her eye. The very next film has him bash a rocker chick with her own electric guitar.
 * The Town That Dreaded Sundown has a particularly infamous kill which involves the Phantom stabbing a woman to death using a bayonet attached to a trombone. He plays it to make the blade go in and out of her.
 * A character is fried by his own portable electric guitar in Home Sweet Home.
 * Mighty Morphin Power Rangers: More like "Instrument of Destruction": When Ivan Ooze says to Zordon, "It's time... to pay the piper," Ooze takes out his piping flute and plays a bit like a literal piper before using the flute's electric powers to damage the entire Command Center and weaken Zordon to a withering mortal.
 * The City of Lost Children has a music box that controls a circus flea, making it inject its host with a nerve agent. The affected person then turns violent and attempts to kill whoever they happen to be with.
 * In Wristcutters: A Love Story, Eugene electicutes himself with an electric guitar and a bottle of beer.

Literature

 * In the Fables novel Peter and Max, Peter Piper ends up killing  with a magic flute.
 * The novel Mothstorm by Philip Reeve has hostile aliens whose primary weapons seem to be sedative-tipped darts blown from things that are consistently described as looking like bagpipes.
 * In The Tragedy Of Y (Ellery Queen writing as Barnaby Ross), one of the murder victims is smacked in the face with a mandolin. (Twisting this trope a bit, the blow wasn't fatal, but did set off a fatal heart attack.) This turns out to be a clue to the murderer's identity.
 * In Juliet Marillier's Bridei Chronicles, Faolan is a musician and an assassin, and he strangles someone with a harp string at one point.
 * The end of Friday the 13th: Carnival of Maniacs has Jason going on a rampage at a music video recording he was being used as a prop in while comatose. He kills one of the band members by throwing a cymbal with enough force to slit the guy's throat.
 * A character is killed by having a drumstick launched into their chest by an explosion in the main character's vision at the beginning of Final Destination: Dead Reckoning. Later book Death of the Senses has a guy get decapitated at the jaw line by a platinum record, also launched through the air by Stuff Blowing Up.
 * In the Star Wars Expanded Universe, Mandalorian instruments can often double as these. Their idea of a flute has a sword blade attached.
 * In Star Trek novels (building on background material from the Original Series films), the Andorians often carry a flabjellah - a combination sidearm and musical instrument.
 * In Joe Abercrombie's Best Served Cold, the main characters hire a band of thugs who pose as musicians. One of the thugs has his lute built around an axe, on the theory that the lute will break on impact, leaving only the axe in his hands.
 * During the final battle of the first Bedlam's Bard novel, witch/musician Beth Ketraine defeats The Dragon by clubbing her over the head with a guitar.
 * The Jennifer Morgue by Charles Stross plays on this; Bob's girlfriend, Mo, carries a Zann-model violin that she wields like a weapon. In an amusing Shout-Out to Woody Guthrie, the violin has "THIS MACHINE KILLS DEMONS" written on it.
 * In the Phryne Fisher mystery The Green Mill Murder, the mute in a cornet is used as a blowgun.
 * One of Samuel R. Delany's Nova protagonists has senso-syrinx, a complex futuristic instrument capable of projecting holographic images, complete with sound and odours. The thing is, it includes a laser to create holograms, has a very sharp focus and runs on near-inexhaustible batteries. As the bad guys learn the HARD way, with it's maximum output focused on a person, it can knock them out with horrible stench, blow their eardrums out and not only blind them with a laser, but set them ablaze.

Live Action TV

 * Get Smart had a gun hidden in a violin, and a double-barrelled flute that acted as an airgun.
 * In The Goodies episode "The Stolen Musicians", the Goodies use a euphonium as a cannon, only to be outgunned by the Music Master's pipe organ that doubles as a multi-barrelled artillery piece, but are saved when the symphony orchestra arrives shooting bows from their violins.
 * Ibuki of Kamen Rider Hibiki has a gun that can transform- by shifting the parts around- into a trumpet. It actually works in reverse from normal: he uses the gun to implant bullets in the Monster of the Week (who is naturally Immune to Bullets) then switches to the trumpet to create a resonance that blows it up.
 * All of the Riders use these. Hibiki straps a taiko drum to the monsters and proceeds to beat them to death with taiko drumsticks (and even without the drum, the drumsticks can shoot fireballs), and Todoroki uses an electric guitar that doubles as an ax.
 * It can get fairly silly with some of the minor Oni Riders, who use weaponized tubas and triangles.
 * The Kamen Rider 555 Hyper Battle DVD had the Faiz Sounder, a boombox that transformed into a powerful sonic cannon. This was the winning contest entry Toei had for a new weapon for Faiz, which like all other weapons in the show, was based off a real world object.
 * On an episode of The Muppet Show there was a sketch featuring a performance of the William Tell Overture that ended with the cellist firing the bow from his cello to shoot an apple off Beauregard's head.
 * In the Doctor Who special "The Christmas Invasion", the robot Father Christmases wield brass instruments that double as weapons, including a trombone-flamethrower.
 * In the M.I. High episode "The Visit", the enemy spies use an alpine horn that spews knockout gas.
 * An episode of Friday the 13th: The Series featured a cursed violin. The violin itself wasn't used as a weapon, but the blade hidden in the bow certainly was.
 * One enemy agent in The Avengers had a clarinet with a blade that would slide out of the bell when the right key was pressed. He used it twice: once to kill a fellow he caught trying to steal the McGuffin, and once in an unsuccessful fight with Steed ... who remarked that the instrument probably played "sharp."
 * In Community episode English as a Second Language Chang wields a key-tar like a battle axe.
 * Burt uses a guitar as a club to take out Smokey Floyd.

Mythology

 * Greek Mythology time: According to one myth, the lyrist Linus was the music teacher to Hercules. After criticizing Hercules' playing a bit harshly, Herc took Linus' lyre and bashed its owner's head in. The first evidence of this story is in vase-paintings of the 5th century BC, making this one Older Than Feudalism.

Professional Wrestling

 * Professional wrestler Jeff Jarrett would occasionally indulge in smacking his opponents with a nonfunctional guitar.
 * Before J-A-Double R-E-Double T, there was the Honky Tonk Man. Though the whole "smack you with the guitar" thing took a nasty turn when Honky hit Jake "The Snake" Roberts with a real guitar and severely injured him -- which was the beginning of Roberts' many problems with painkillers.

Tabletop Games

 * Noise Marines in Warhammer 40,000 can do this. If blasting the enemy with The Power of Rock doesn't work, they can simply beat the enemy to death with their daemonic, spiky guitars and superhuman strength.
 * The Exorcist applies this principle to a pipe organ... then attaches it to a tank. Too bad the Exorcist couldn't hit the broadside of a Titan.
 * In Silver Age Sentinels, Feedback is a rock star turned superhero who wields a guitar that focuses his powers into energy blasts.
 * In Dungeons and Dragons, the horn of blasting is a very powerful but very dangerous magical item. Doing thunder or sonic damage (depends on the Edition) its potent blast of sound can flatten small buildings and bowl over whole groups of mooks with ease. However, each use per day beyond the first gives it a cumulative chance to explode (usually 20% per additional use) possibly killing the user.

Video Games

 * Eiko from Final Fantasy IX used a flute as a weapon - both by whacking people with it and by playing it as part of her Summon Magic.
 * In Shadow Hearts 3, the last party member you acquire is a Mariachi with an arsenal in his guitar. Shotgun, flamethrower, multiple rocket-launcher rack, machine gun... all packed into a single guitar which, oddly enough, still sounds just as sweet.
 * In Okami, Waka has a flute that turns into a Laser Blade.
 * Also, the imps you encounter in the first sections of the game use flutes, shamizens and drums as weapons.
 * This is the entire premise of the music/fighting game Battle Of The Bands.
 * In Illusion of Gaia, the main character uses a flute as his primary bludgeoning weapon.
 * Lyude in Baten Kaitos uses a weird trumpet/gun as his weapon. His Magnus cards reveal that it's actually a weapon specifically designed for use by assassins. No comment on why the Honor Before Reason party member is using it.
 * One of the joke weapons in Disgaea 4: A Promise Unforgotten is an electric guitar.
 * Certain classes in Final Fantasy Tactics Advance and Final Fantasy Tactics A2 can equip musical instruments as weapons. There's nothing particularly clever about how they use them in combat though: they just bludgeon the enemy over the head. Like the books, staffs and rods, you're generally supposed to assume that said items are primarily used as tools for casting skills, and not bludgeoning weapons.
 * In Final Fantasy Tactics, Bards could use harps to deal ranged damage that appeared to be the notes causing the damage. Bard Songs were typically of the beneficial variety.
 * I-No of Guilty Gear uses a shapeshifting electric guitar. She can either smash people with it, or create cacophonic sounds to defeat her opponents.
 * Zhen Ji of Dynasty Warriors 4 and DW 5 has a flute as her signature weapon. Typically this just means she whacks people with it, but her special attack involves playing a devastating note.
 * Motochika Chokosabe from Samurai Warriors 2/ Warriors Orochi 2 rocks out on his shamisen to attack.
 * Somewhere on the border between this and Senseless Violins, there's a brief cutscene in Shogun: Total War that shows a ninja assassinating his target with a poison dart blown out of a flute.
 * The seventh game in the Touhou series features a stage boss the Prismriver Sisters, a trio of poltergeists who generate their "danmaku" through music. Admittedly, not the straightest of examples, as danmaku is explicitly stated in supplemental material to be non-lethal, but they do threaten to eat prepare as party snacks at least one protagonist, so, yeah.
 * One of the power-ups in Total Overdose are two guitars that act like machine guns, in a clear homage to the Once Upon a Time in Mexico example above.
 * A couple of characters in Eternal Sonata use musical weapons, such as a clarinet/gun/mallet and a fencing rapier shaped like a conductor's baton.
 * Demyx from Kingdom Hearts on top of using his sitar to create water-based minions and cast various water-based spells, he can bludgeon his enemies with it.
 * Equipping Xigbar with the Mystery Gear in 358/2 Days makes him wield a pair of trumpets in the stead of his Arrowguns. They shoot musical notes, accompanied by the appropriate sound effects.
 * In Monster Hunter, Hunting Horn's are almost as effective as hammers at breaking body parts.
 * Rocketbilly Redcadillac's electricity-shooting guitar from Gungrave: Overdose. The artbook says its name is "B.L. 20,000V". ("Blue Lightning 20,000V"). Made by the Electrigger Company! Despite being weak with melee fighting, Billy can do a little dance that causes his guitar to spin around him, bludgeoning mooks.
 * Mizuka Nagamori of Eternal Fighter Zero may prefer to create exploding music notes, but she has no problem bludgeoning you with her cello. Her cello bow can also function as a boomerang.
 * Kaph's guitar doubles as a gun in Luminous Arc 2.
 * From the same game, Sadie, the Breeze Witch, uses a trumpet as a weapon. It's surprisingly effective.
 * Some of the ranged weapons in Kingdom of Loathing are musical instruments that double as weapons.
 * The Stolen Accordion is the default weapon of KoL's bard class, the Accordion Thief. The Accordion Thief also has singing as a basic attack.
 * In Devil May Cry 3, one of the coolest available weapons is Nevan, a guitar that shoots lightning, controls bats, and turns into a scythe.
 * In Brutal Legend Eddie can electrocute people with his guitar.
 * Left 4 Dead 2 allows players to wield an electric guitar as a melee weapon. It makes a satisfying kabong noise when you hit things with it.
 * In Team Fortress 2, the Engineer can now use his guitar as a taunt kill, which uses the same noises from Left 4 Dead 2.
 * Possibly inspired by the shakuhashi from above, Suzume in Mini Ninjas uses her flute both as a close combat weapon and an improvised boat paddle.
 * Though she's primarily a Musical Assassin, Yurika Kirishima of Project Justice is not below using her prized violin as an épée when in combat.
 * The Arcanite Ripper of World of Warcraft fame is an axe that doubles as a guitar.
 * The AI Weapons in Metal Gear Solid: Peace Walker are primitive Vocaloids put into big, heavily-armed tanks.
 * Bards and their more powerful counterparts in Ragnarok Online fight with their musical instruments. What doesn't entirely make sense is how they manage to throw/shoot arrows (depending on the skill) by swinging it at their opponents. They can also be Musical Assassins by spamming songs, but it takes more effort, mana, and time.
 * Kimmy Howell of No More Heroes 2: Desperate Struggle has a flute that turns into a double-ended Laser Blade.
 * ANYTHING can be used as a weapon in Dead Rising. Guitars and other musical instruments count as "anything".
 * Talim of Soul Calibur IV uses a pair of ocarinas as her joke weapons.
 * In Arc the Lad, Poco's weapon of choice is a pair of cymbals.
 * Same goes for Mallow in Super Mario RPG.
 * Amy from Grand Chase has this option for both 2nd and 3rd class. In one form she will play the instrument, in the other she beats up the target with it.
 * Hyperdimension Neptunia has 5pb who uses guitars as her weapon, to use a special attack she will play it. But in normal hits she will smack the target with it.
 * The Hero from Ephemeral Fantasia has a sword hidden in a guitar.
 * The second boss of Zool is an electric guitar that rains fireballs on you. You also face violins that shoot their fiddles at you.
 * There was an old Christian-themed computer game (called Knights Of Virtue if I recall) which featured among its weapons the "trump of fire" and "trump of lightning", a pair of trumpets that, if pointed at your enemy and played, wouldn't make a note (just a "ffffff" noise like someone blowing into a tube, fancy that), but would rain down fire or lightning on them.
 * Terraria added a weapon called the Magical Harp. Oddly enough, it can be used to kill The Destroyer in a matter of seconds. Beware the Spoony Bard.
 * Terraria added a weapon called the Magical Harp. Oddly enough, it can be used to kill The Destroyer in a matter of seconds. Beware the Spoony Bard.

Web Comics

 * In Girl Genius, Sleipnir O'Hara has the 'Hot Pipes', a set of bagpipes that shoot fire.
 * King of the Unknown stars a still-living, 'No Celebrities Were Harmed' incarnation of Elvis Presley known as "the King." His signature weapon is a magical guitar, which he uses to a) bash supernatural creatures' heads in and b) harness the almighty Power of Rock.
 * Telv's steel-plated banjo from Planescape Survival Guide .
 * Keychain of Creation has the deathknight Resonance Ben, who just recently upgraded to an entire band.
 * As the example mentioned above, piano wire: In a flashback arc of And Shine Heaven Now, after Jeeves refused to teach Walter a complicated technique with their weapon of choice, monofilament, Walter nicks the piano wires from Bertie's piano to practice on his own, and later uses it to hold back a vampire while the others escaped.
 * In Rusty & Co., Roxy Casbaugh uses her lute to K.O. an attacker. Percussively.

Web Original

 * Survival of the Fittest spinoff The Program had John Ferrara use, of all things, a banjo to beat Matthew Gourley to a pulp. On the main site we have Isabel Guerra making a shiv out of a trumpet and broken piece of glass. It's called Partario.
 * The Ongoing Saga of Fritz the Unfortunate follows a troupe of musicians who all wield these.

Western Animation

 * El Kabong, Quick Draw McGraw's alter ego, wielded a guitar (which he called kabonger) that he would just hit criminals with. Worked every time.
 * Which then came up in Harvey Birdman, Attorney at Law, where guitars served as a metaphor for concealed weapons.
 * Sonic Underground had Sonic's guitar, Sonia's keyboard and Manic's drumkit. The latter was the only one not to function as a laser. Instead,it caused EARTHQUAKES.
 * In the first of that Chaos Emerald Trilogy, Manic was able to shoot a laser, ONCE in the entire freckin series.
 * The King from Darkwing Duck has a guitar that fires destructive energy beams.
 * In The Simpsons episode "Homer of Seville", Homer's stalker Julia uses a blowgun concealed in a conductor's baton.
 * The season finale of Metalocalypse had Skwisgaar Skwigelf kill several invading Revengencers with his guitar. The guitar is not damaged at all.
 * He also owns a guitar made from the wood of the cross Jesus was crucified on.
 * In the Shaggy & Scooby-Doo Get a Clue! episode "Operation Dog and Hippie Boy", the evil hippie robot Groovy Don carries a laser beam firing guitar.
 * Transformers Animated's version of Soundwave has an electric guitar that turned into his attack bird Laserbeak. At least until Prime used him as an axe. (Sorry!) He also had Ratbat, who turned into a keytar.
 * In Silverhawks, Bluegrass wielded a sonic blaster guitar as a weapon while his Evil Counterpart Melodia had a keytar that fired laser blasts shaped liked musical staves.
 * Got an Actor Allusion Shout-Out in the Galaxy Rangers ep "Battle of the Bandits" where the Rangers and a pack of Slaverlords started firing their "modified" guitars at one another. Doug Pries played both Bluegrass and Gooseman.
 * Ember Mclain from Danny Phantom could smack people around with her electric guitar.
 * The Cosmic Guitar from Loonatics Unleashed which, amongst its other powers, could fire energy blasts.
 * In Aqua Teen Hunger Force, Ignignokt and Err had the Foreigner Belt, a guitar-shaped belt that causes damage effects according to Foreigner lyrics.
 * The Music Meister from Batman the Brave And The Bold had a smoke-spewing pipe organ he used to cover his escape and laser firing microphones that formed part of his Death Trap. In fact, any weapons he had followed this theme.
 * And in "Night of the Batmen!", the Vigilante has guitar that doubles as a rifle.
 * Class of 3000: In "Funky Monkey", Tamika uses her harp as a bow to fire a drumstick at Lil' D.
 * Five from Generator Rex wields an electric guitar as her primary weapon.
 * Val Hallen, the Viking God of Rock, from the "Justice Friends" segment of Dexters Laboratory, wields a mighty axe.
 * Marceline the Vampire Queen has a guitar shaped like an axe. It tends to get used like a guitar, though, which is not to say it hasn't been involved in asskicking.
 * If her father is to be believed, the instrument started life as an axe and was turned into a guitar later.

Real Life

 * The shakuhashi (Zen bamboo flute) of Japan is a bit of a subversion; initially it was just a normal flute, no military applications attached. However, when the samurai that normally used it became unemployed and unable to use their swords by law, they beefed the flute up to be strong enough to be used as a club, thus becoming their main weapon of defense.
 * A sufficiently large hard instrument case works as a decent Improvised Weapon, if you're not too worried about the instrument inside. Actually, scratch the "sufficiently large;" it hurts plenty to be hit in the head with a flute case.
 * And then there's the 1812 Overture. No less than 16 cannon shots are written in that piece.
 * ACDC incorporated cannons into their stage act for "For Those About to Rock".
 * Also by AC/DC, the cover for If You Want Blood You've Got It.
 * Piano wire can be used as a garrote.
 * Gene Simmons' bass looks like an axe. Unfortunately it only functional as a bass.
 * The shawm (an ancestor of the oboe) was used as a weapon from time to time.
 * An unspecified spy service apparently at least once modified a flute to fire a single pistol round. The instrument was still fully functional for musical purposes.
 * The Clave. Although listing this as real life could be a stretch.