Whip Sword

What's better than a whip or a sword? A whip sword, of course! They have the flexibility and long reach of a whip and the cutting power of a sword, meaning that all sorts of fancy tricks can be done with them while cutting people to pieces.

This type of weapon often falls squarely into Awesome but Impractical, where you'd need a pretty impressive engineering setup to create a mechanism and spring capable of holding the sword in sword-form without violating basic structural integrity and capable of sending it out as a whip. As of yet, no one's managed to make a working model of such a weapon in Real Life (though some come close in principle), but fiction usually Hand waves any structural issues through magic. The closest practical Real Life equivalents, like the chain whip and Indian Urumi, usually lack the cutting power of a sword or the reach of a whip.

But then again, making a whip sword is only half the battle, since you would need extensive training to actually use it or else you'd be more likely to hurt yourself than anything you're trying to hit. This is not impossible in real life, however, as demonstrated by the use of the Urumi weapon by the Indian Rajputs but will likely speak more of the extreme skill of the wielder than any inherent practicality.

But hey, you have to admit they look cool, hence this is a Sub Trope of Impossibly Cool Weapon.

Anime/Manga

 * Battle Angel Alita attepts a realistic-ish approach with a character wielding a highly magnetic sword coated in iron filings which extend to a whip when she swings it at high speeds. (She also ups the Beyond the Impossible quota by using said whip to aim seven bullets at various weak spots on an enemy's face and igniting them simultaneously, but that's neither here nor there.)
 * Renji's Zabimaru in Bleach turns into this in its shikai form, and the bankai is this to a factor of 100 with a snake's head.
 * Zabimaru's Super Mode doesn't usually cut as much as it crushes with sheer bulk, unless Renji sharpens it during a Finishing Move. It usually rams enemies head-on like the snake it resembles.
 * Also, Rose's Kinshara is a pretty a whip when released.
 * Hibana from Deadman Wonderland wields a BFS whip sword similar to Renji's. Very impressive for an approximately eight-year-old insane Creepy Child.
 * Kuroki of Blazer Drive's BFS has recently been revealed as one of these; it too looks very similar to Renji's (the "sword" half looks a lot like Allen Walker's BFS).
 * Shizuru Fujino in Mai-HiME can separate her naginata into sections and use it to whip an enemy and grab people, making her extremely deadly whenever she gets mad.
 * Mai-Otome's Shizuru has a double-bladed sword that acts the same way, but has a much longer blade.
 * Magical Girl Lyrical Nanoha As has Signum, whose sword can take the "Schlangenform" (Snake form) to split into segments and be used to form a whirlwind-like effect.
 * She can also light it on fire.
 * Cho, the sword Otaku member of the Juppongatana in Rurouni Kenshin possesses a super-thin sword that can be utilized as a whip.
 * A Filler character in Naruto possessed one, using his chakra to control it.
 * Akatsuki member Sasori usually uses a puppet named Hiruko which has a poison whip-sword for a tail (Sasori mean "scorpion").
 * Kimimaro has a rather morbid variation: he makes weapons out of his own bones, and one thing he makes it a Whip Sword by pulling out his own spinal cord.
 * Jakotsu in Inuyasha has a sword referred to as the Jakotsu-to ("snake bone sword") with this capability. It consists of a crescent-bladed sword with about a dozen more crescent-blades linked tip to tip attached to it, allowing him to flick out a chain of cutting edges. Interestingly, it's the only (regularly-used) sword in the show that doesn't have any magical powers or get a magical upgrade.
 * A rather impudent bandit in Claymore tried to use one such sword to bully Teresa. He may have had time to regret it.
 * Van's sword in Gun X Sword is a partial example; while it's flexible enough to wrap around his waist, he never attacks with it until it's stiffened into its full sword form.
 * Just to clarify then, this character's weapon starts floppy, but after he whips it out it becomes stiff and he uses it to (I'm guessing) thrust at people. I guess Freud Was Right.
 * Shenhua from Black Lagoon fights with twin whip kukri. She's good enough to take people's heads off with them from thirty feet away.
 * Note that these are a much more practical version of a Whip Sword. They're just kukri knives tied to a piece of rope tethered to Shenhua.
 * Gundam Wing has a couple of mecha that wield heat rods, which are essentially giant whips made up of conjoined blades - sort of like a Whip Sword that can't become a sword. Oh yeah, and it can be super-heated too.
 * The version of Epyon from SD Gundam Force actually uses a Whip Sword, which is in effect the original Epyon's two main weapons (heat rod and large beam sword) combined into one.
 * From SD Gundam BB Senshi Sangokuden, Kakouton Giros wields a sword which separates into a chain-whip sword.
 * Ohm of One Piece had a sword with a Milky Dial in the hilt that could shape-shift into many forms. He primarily turned it into a flexible strip of iron to use as a whip, while using his mantra to pinpoint an enemy's location.
 * Snake from movie 3 has a more standard snake sword.
 * Princess Tarta from Magic Knight Rayearth has a sword that can transform into a whip.
 * The titular character in Iria: Zeiram the Animation wields a whip sword, though she vastly (and justifiably) prefers guns and grenades.
 * Jil gets one in The Tower of Druaga ~The Sword of Uruk~.
 * Spider Riders's Prince Lumen has one of these, though he seems to use it more as an extending-length sword than an actual whip. Beerain owns the real thing.
 * Knight in the Weiss Kreuz Radio Drama Crashers: Knight and Ran uses a Whip Sword referred to as a "cordon d'argent."
 * Kyouko Sakura in Puella Magi Madoka Magica uses a chain-spear as her weapon, which works under the same premise.
 * Fay uses one in Tsubasa Reservoir Chronicle while in Infinity.

Comic Books

 * Snapdragon from Kabuki uses one.

Film

 * The French film and book Brotherhood of the Wolf had a segmented bone sword that was utilized this way.
 * Savior Of The Soul has not a whip sword, but a yo-yo sword.
 * Roxy's weapon of choice in Scott Pilgrim vs. the World is one of these, worn as her belt.
 * If it helps, it doesn't retract into sword-form, it's just a bladed whip that she swings around.
 * Anita Mui's chracter from The Heroic Trio has one that can go from a straight blade to a Whip Sword.

Literature

 * Shannon fights against someone with a Whip Sword in the first Scrapped Princess novel.
 * One of the Denarians in The Dresden Files book Death Masks has long ribbons of metal for hair that act just like a whip sword.
 * As is the "Cobra" that Case buys to use for a short part of Neuromancer.
 * This was actually a Spring baton with a slightly different name.
 * Similarly, Konrad the assassin in All Tomorrow's Parties carries a urumi-like flexible blade inside his belt, mechanically triggered with a device in the buckle. Technically we never "see" this employed, but we get a very good idea what his imminent plans are for it before the Fade to Black...
 * The Star Wars Expanded Universe has lightwhips, which are usually explained as being actual, physical (metal) whip strands - much more similar to a Warhammer 40K energy blade than a standard lightsaber. It's incredibly rare - only one character has used it on a regular basis.
 * There are also the Vong amphistaff and tsaisi, which get a pass for being actual living creatures (and still take substantial training to use well).
 * Whip knives were developed by the people of Port Kar in Gor. The last 18 inches of the whip has twenty small knives set into it, they are apparently quite effective.
 * The spear-whips in Minidoka: 937th Earl of One Mile Series M by Edgar Rice Burroughs.

Live Action TV

 * In Metal Heroes, Space Sheriff Shaider used a laser sword that he could transform into a laser whip at will.
 * In Kamen Rider Ryuki, Kamen Rider Raia wields one of these.
 * In Kamen Rider Kiva, Taiga Nobori/Kamen Rider Saga has a rapier-like weapon that can convert into an energy whip; he continues to use it even after . The Blue Sky Organization circa 1986 gives its warriors a Swiss Army Weapon that can go from long dagger to Whip Sword.
 * In Kamen Rider Den O, much of the variants to Sword Form's Extreme Slash has Den-O flinging the blade around, with electricity tethering the blade to the hilt.
 * In Power Rangers Wild Force, the Wild Force Megazord's Sword and Shield Mode used one of these. (a transformed robot elephant trunk)
 * In fact, most combinations using the Elephant Zord can count as this.
 * Samurai Sentai Shinkenger obliges this with the Kyoryumaru, which is used by any Shinkenger in Hyper Form.

Tabletop Games

 * Probably drawing their inspiration from the William Gibson example above, the monofilament whip is a staple weapon in many cyberpunk roleplaying games, especially Shadowrun.
 * In the older editions of Warhammer Fantasy, this was essentially one of the possible powers that could be enchanted into a sword by the touch of Chaos. It didn't physically change, but the blade could extend and bend like it was a prehensile tongue made of razor-sharp steel.
 * In Warhammer 40,000, the fifth edition Dark Eldar have razorflails used by their wych cults.
 * The Urumi is available in GURPS: Martial Arts, sadly it has none of the strengths of a whip and none of the strengths of a sword.
 * In the Iron Kingdoms setting the Satyxis aiders of Cryx and Bloodrunner master tormentors of the Skorne use a variation of this. Neither have swords that transform to whips, but the Satyxis have whips with sharp blades attached to them throught their lenghts and the master tormentors have whips that are comprised of circular blades linked together.
 * There is a drow weapon called a lashwhip (redundant, I know) in the Dungeons and Dragons 3.5 supplement Arms and Equipment Guide, which is described as a whip with lots of shards of metal and glass protruding from the lash. If a non-drow uses it, it magically attacks them instead of their intended target.
 * The obscure book Eberron Torn Asunder provides us with the chain blade, which is essentially this trope played entirely straight. It's also a noted Game Breaker as being a one handed reach weapon with a long sword's damage and the single largest critical range in 3.5 at a staggering 17-20 standard. In other words its everything a melee combatant needs in a one handed weapon and then some with the only downside being that it's exotic and the sourcebook is almost impossible to find. Oh, that and no DM in their right minds use the thing.
 * The Scorpio Ars Magna school in Anima Beyond Fantasy. Wielders need a basic understanding of Supernatural Martial Arts to use it. In the game's offical setting Lilith, one of the four Knights of the 7th Heaven, uses this weapon.
 * Planeswalker Gideon Jura from Magic the Gathering wields a three-bladed whip they call a 'sural' or 'urumi', and it is believed they were referring to the Indian chuttuval.
 * Violet from Summoner Wars uses this.
 * Ultimate Combat, a Pathfinder splatbook, features a "Scorpion Whip." It is described as having a "series of razorsharp blades and fangs inset along its tip" can deal lethal damage, and is not hindered by armor, unlike a normal whip.

Video Games

 * This is Ivy's signature weapon in the Soul Calibur series, dubbed the "Snake Sword" in game. The name of the one she uses most often is "Valentine" though others are useable in gameplay (Though if they actually exist in universe aside from the "Prototype Ivy Blade" mentioned below, or Soul Edge and Soul Calibur in the form of one, is debatable...)
 * Her joke weapon is a mechanical failure of this concept, though she still manages to use it to fight. The actual sword uses alchemy/magic to work properly, making the sword itself sentient.
 * Her joke weapon becomes a "Magical Sausage" in Soul Calibur IV.
 * Create a Soul characters in 3 also have the option of a similar sickle, except that nearly all of its attacks use it as a whip. Its best use? Making Indiana Jones and Franziska Von Karma.
 * Takenaka Hanbei from Capcom's Sengoku Basara 2 (known in the West as Devil Kings 2, which is basically Capcom's version of Samurai Warriors on crack and steroids) utilizes a whipsword to devastating effects.
 * Kaihime from Samurai Warriors 3 uses one of these.
 * Kratos carves a bloody swath through Ancient Greece using one in God of War, though it's actually swords chained to him.
 * The Dark Prince in Prince of Persia uses a weapon like this called the Daggertail as his main weapon, and is very, very efficient with it.
 * All of Jacques Blanc's weapons in Onimusha 3 are some variation on the Whip Sword, ranging from spears to maces to the regular sword.
 * In Ninja Blade, one of the three weapons available to you is a pair of knives with detachable blades that are attached to the hilts by wires. As you would expect, they deal very little damage, but do so many times in a very short amount of time. They can also be used as grappling hooks.
 * Janne from World Heroes.
 * Beaten out by one year as Ur Example by the Great Dragonian, probably the coolest boss in Capcom's arcade "hack'em up" The King of Dragons. The game didn't appear on home consoles until three years later however.
 * Nash Latkje, from the Suikoden series, is a man of many hats. In addition to training with The Howling Voice Guild before becoming a spy a la James Bond--with a matching set of womanizing ways--he has, at points, used a Whip Sword named Groß Fluß ("Gross Fluss", "big/great river"). While, at first glance, it seems to be a good weapon for a discrete spy, being easily concealed and flexible enough to be useful in closed spaces, Nash will warn allies to leave the room when he uses it, because it apparently triggers some sort of magical bloodthirst.
 * Soma Cruz in Castlevania: Aria of Sorrow and Dawn of Sorrow prefers swords instead of Belmontean whips, but there is a Whip Sword in both games if you want something with some reach.
 * Due to the way Soma uses them in Castlevania: Dawn of Sorrow, the whip swords essentially function as overly-complicated rapiers.
 * Overly complicated rapiers with Sparkles! At least, the Nebula (the most powerful such weapon) is.
 * In Ratchet and Clank Up Your Arsenal, one of the weapons is a plasma whip. It's like the lightwhip from Star Wars, only ten times more awesome. Chainblade, a boss in Going Commando, is an even better example, wielding two Whip Swords..
 * Saber Alter in the Heaven's Feel scenario of Fate Stay Night gets one of these when she becomes a Mighty Glacier, and it reappears with her in Battle Moon Wars.
 * Specifically, she uses the energy from her sword like this. The sword itself is basically a palette swapped evil version of, and is still as solid as it was before.
 * Invidia, one of the Black Knights in Eleven Eyes, wields a whip sword that resembles a human spine. It's very destructive.
 * While it's neither a whip nor a sword, Billy Kane's bo certanly qualifies, as it can also extend into a 3-section staff when necessary, yet it never does so when he doesn't want it to no matter how much he flails it around. The explanation? It's more or less implied to be held together by industrial-strength springs, and he's so ridiculously strong that he can cause the joints to extend simply by thrusting it forward with one arm.
 * Sion Eltnam Atlasia wields a monofilament whip called the Etherlite in Melty Blood.
 * One of the strongest weapons available in Tales of Vesperia for Rita is one of these. As a Shout Out, it's named the Ivy Sword.
 * Every melee weapon type in Aion has extend-able long-range versions.
 * Avril's Absolute Zero ARM in Wild Arms 5, though she only uses its whip form in her Finest Arts and some of her Combination Attacks.
 * Garland from Final Fantasy I has one of these in Dissidia Final Fantasy. Or, to be more precise, he has a sword that can transform into two swords, a hammer, a lance and a whip.
 * Merietta Lixiss, the last member to join your party in Atelier Iris: Eternal Mana (unless you go to the bonus dungeon after beating the game once to get another character) fights with a Whip Sword that has a strange star shaped point. Also, she can conduct Lightning through it.
 * Roxie Richter, the 4th boss of Scott Pilgrim vs. the World: The Game, uses a whip katana. A compromise between the books, where she uses an ordinary katana, and the film where she uses a bladed whip.
 * In Prototype, Alex changes his arm into one.
 * In Resident Evil 5,  gets a massive tentacle with sharp chunks of metal embedded into it for an arm and swings it fast enough to resemble a gigantic living chainsaw. That... thing also doubles as a flail, a drill, a sling and a pogo stick.
 * This is Dante's main weapon in Dmc Devil May Cry.

Webcomics

 * From A Modest Destiny, The Crimson Skull's signature weapon, the Chain Sword.

Western Animation

 * In Zorro Generation Z, the Scarlet Whip wields twin laser whips.

Real Life

 * The Aara sword, wielded by Indian Rajput warriors, is basically a 6-foot ribbon blade.
 * If you don't need to ever pass your weapon off as a rigid sword, there's the Indian urumi, a multi-tail whip made of spring-steel blades. Its actual combat effectiveness remains hotly debated, as it was never widely used, and any combat forms which utilize it are, by definition, almost impossible to demonstrate in a sparring match without serious risk to one or both combatants.
 * The Romans had Scourges, whips with metal or glass shards tied in. Notably, they were used as torture implements, not proper weapons.
 * Chinese martial arts include the 9-section steel chain whips as part of their arsenal. As awesome as it sounds, it doesn't have that much killing potential.