[[quoteright:330:[[VideoGame/CastlevaniaSymphonyOfTheNight http://static.tvtropes.org/pmwiki/pub/images/ScyllaCastlevania_6814.jpg]]]]
[[caption-width-right:330:[[Literature/TheOdyssey Siren]], she ain't.]]

->''"Oh, what do you know, it's a uni-whale-scorpio-Pega-squid-icorn-girl. What are the odds. You know, taken all together, it's more ridiculous than scary. I guess it doesn't have a cumulative effect."''
-->-- '''Malifishmirtz''', ''WesternAnimation/PhineasAndFerb'' episode "Excaliferb"

{{Shapeshifting}} comes in a lot of forms (in every pun-laden sense of the word). Most shapeshifters, however, stick to using a single concrete form at a time; this is true even if they swap shapes quickly during a ShapeshifterShowdown, or when truly skilled shapeshifters [[PartialTransformation mix-and-match elements of their alternate form]] with their [[ShapeshifterDefaultForm normal human form]].

Sometimes, though, a shapeshifter gets the idea that if more is better, why limit themselves to just ''one'' shape at a time? Why not transform into all of their forms, ''all at the same time'', and become the '''ultimate''' ShapeshifterWeapon?

Long story short, [[GoneHorriblyWrong it doesn't work]].

This attempt at creating a unique OneWingedAngel SuperMode will tend to [[GoneHorriblyWrong encounter a slight problem]]: Instead of [[LightningBruiser merging the best elements]] of their various forms into one sleek and awesome HybridMonster, it will ''literally'' combine and merge their various forms together, producing a chimeric monstrosity that only an EldritchAbomination could appreciate. It may feature [[MultipleHeadCase one head from each form]]; all the arms, claws, paws, legs, CombatTentacles, fur, scales, and BodyHorror that goes along with them; a [[PowerGivesYouWings half-dozen]] [[GoodWingsEvilWings mismatched wings]], and -- like the proverbial cherry on top -- the original head and/or upper torso of their ShapeshifterDefaultForm.

Despite the patchwork nature of this form, it does still have ''[[PowerUpgradingDeformation some]]'' advantages. Like the [[RuleOfScary power of intimidation]], its [[ShapeshifterBaggage supermassive]] [[MightyGlacier size]], and an AnatomyArsenal stocked with every variety of BreathWeapon known to man ([[SerialEscalation if not more]]), and can easily wipe out entire armies that approach anywhere within its InstantDeathRadius.

However, the drawbacks are just as significant: because MonstrosityEqualsWeakness, this form likely has [[MasterOfNone severe drawbacks]] over [[MultiformBalance the individual component forms]], and it's likely to be [[PowerDegeneration highly unstable]] or prone to [[ClippedWingAngel catastrophic failure]]. If the shapeshifter can't keep focus he may enter a SuperpowerMeltdown where the LossOfIdentity causes the [[OrganAutonomy body's components to attack each other]], with the potential to become the [[TakeOurWordForIt very goriest]] of {{Shapeshifter Swan Song}}s.

Because of all the above drawbacks, this is sometimes used as a nasty {{curse}}, typically a BalefulPolymorph that [[ShapeshifterModeLock Mode Locks]] the victim. The independent body parts in this case are usually [[GuardianEntity Guardian Entities]] outside of the victim's control, but won't attack him or her. They may however respond to his or her emotional cues, like a gorgon's snake hair or an owner's pets.

The Shapeshifter Mashup is usually the penultimate step in the BishonenLine, right before a return to a humanlike appearance.

Compare and contrast the "Mixed Form" variety of FusionDance, where a single character combines multiple transformations to create a new form, and PartialTransformation, where the shapeshifter adds elements of one form to another form. This might be considered a gory way to demonstrate HybridOverkillAvoidance.


[[folder:Anime and Manga]]
* In ''Manga/{{Bleach}}'', the Arrancar Aaroniero Arruruerie has absorbed the powers of thousands of Hollows, and for his final attack in his released form he transforms into a monstrosity combining many of these powers.
* Raphaello in ''Anime/BtX'' exhibited traits of every living being it had absorbed.
* In ''Manga/{{Inuyasha}}'', recurring enemy Naraku frequently uses a mash-up form of the demons he's [[AppendageAssimilation assimilated]]. This is especially true during his periods of weakness (something all half-demons go through regularly), when he becomes stuck as a gigantic mass of organs and tentacles that can't even move.
* Mr 2 Bon Clay from ''OnePiece'' once used a mash-up of the most ridiculous facial features he knew during his fight against Sanji, in an attempt to throw him off-guard with laughter. Unfortunately, 90% of said features are ''[[ShapeshifterDefaultForm his]],''[[note]]The only part that wasn't was Usopp's nose.[[/note]] which was so stupidly pointless that it just made Sanji angry.
* Aptom from ''Manga/{{Guyver}}'' can ([[BodyHorror quite graphically]]) absorb Zoanoids into himself to take on their form and powers, but for combat he usually takes on a unique form which combines as many of the best traits he has 'eaten' as possible, which he updates from time to time. While these hybrid forms are generally quite sleek in appearance (sometimes moreso than the original creatures), [[MindControl "Evil Aptom"]] looks more like a traditional abomination due to his controller not fully understanding how Aptom's body works.

[[folder:Fan Works]]
* In Roleplay/DCNation, Fauna can use this trick, but it's quite difficult, and runs the risk of [[TheMindIsAPlaythingOfTheBody turning her feral]].
* During the FinalBattle of ''Fanfic/TheLionKingAdventures'', [[spoiler: [[UltimateEvil the Writer]]]] transforms into a chimera that has traits from [[AllYourPowersCombined every other villain in the series]].

* ''Film/TheThing1982's'' final form is this.
* The T-1000 in ''Film/Terminator2JudgmentDay'' has moments of this as it goes through its ShapeshifterSwanSong.

* Happens to Marco involuntarily in ''Literature/{{Animorphs}}'', "The Proposal" when he gets emotional over his dad's remarriage. He morphs a skunk/spider cross, a lobster/osprey cross and a poodle/polar bear cross at various points. He also morphs a trout with gorilla arms, which nearly suffocates him. This is actually a method people who are able to morph can do called the Frolis Maneuver.
** Might also be said of anyone who uses the Frolis maneuver to create a morph of the DNA of several individuals of a species combined.
** Elfangor and Aximill use a downplayed version of this trope, combining human features to create a completely new human appearance.
* In ''Literature/HarryPotterAndThePrisonerOfAzkaban'', Professor Lupin notes this as a potential weakness of boggarts, which are magical creatures that change shape to become the greatest fear of anyone facing them. It therefore pays to approach them in groups, to confuse them; Lupin tells of a boggart who once tried to scare two people at once. One person was afraid of flesh-eating slugs, the other was afraid of headless corpses; the boggart turned into half a slug and didn't scare anyone at all.

[[folder:Tabletop RPG]]
* ''TabletopGame/DungeonsAndDragons'' has multiple types of shapeshifting, some of which replace your abilities and others which enhance them - the latter type (most notably possessed by [[OurWerebeastsAreDifferent lycanthropes]]) can be used in conjunction with another transformation ability to invoke this trope. It's even possible for a creature to become infected with multiple types of lycanthropy (eg. a werewolf wereshark) and transform into multiple Animal or [[PartialTransformation Hybrid]] forms at the same time.
** At high levels the Master Transmogrifist PrestigeClass gains the "Infinite Variety" ability - whenever it transforms into another creature with a spell, it may add one aspect of a second creature whose form it could have taken with that spell.
* This is what the Lunar Knack "Hybrid Body Re-Arrangement" is for in ''TabletopGame/{{Exalted}}''. It allows the Lunar to, instead of shifting completely into a new form, shift only parts of his body into something. A Lunar in shark form could turn its tail fin into a mass of tentacles, its left breast fin into a crab's claw, and the right breast fin into a human arm to wield its favourite sword, while it grows three pairs of giant spider legs and a pair of lungs before topping it off with feathered wings...

* ''Toys/{{Bionicle}}'':
** Krahka attempts to become a fusion of the Toa Metru but she is unable to control their combined powers.
** Done by [[BigBad the Makuta]], on two occasions: first, he [[FusionDance fused with]] three other characters, and ended up being a monstrous combination of their features (In the comics, books and his toy-form, at least. Subverted in TheMovie, where they simply slapped wings to his pre-existing animation model.) The second example is his AlternateUniverse-self, who merged with his entire Brotherhood, to become the only living Makuta.

[[folder:Video Games]]
* A common theory about ''VideoGame/MetroidFusion'' is that the [[EvilTwin SA-X]]'s [[OneWingedAngel penultimate form]] is this (it resembles a Hornoad, the previous form of the X that infected Samus).
* Kefka in ''VideoGame/FinalFantasyVI'' has a half dozen penultimate bosses who are all merged into a grotesque spire of amalgamated shapes. Notably, many of them are clearly modeled on the ''heroes'', making it feel a bit like a ShapeshifterGuiltTrip. The most infamous is the stage right before battling Kefka himself - it's Terra, the heroine, holding Kefka himself in a PietaPlagiarism. That this image appears in a tower constructed by Kefka says a ''lot'' about how far his mind has collapsed.
* In ''VideoGame/FinalFantasyVII'', Hojo's form in the second stage of his boss battle appears as nightmarish conglomeration of himself and his two minions from the first stage (to the extent that his limbs can still be targeted separately). By the third stage, he's got a full-on OneWingedAngel form going and looks human from the waist up again.
* ''VideoGame/CastlevaniaSymphonyOfTheNight'''s Scylla, as pictured above.
* This has become Malfurion Stormrage's default state since he woke up in ''VideoGame/WorldOfWarcraft Cataclysm''. In addition to the stag antlers he's always had, Malfurion now has bear-like feet, claws that look like Wolverine's, and feathers on his arms.
* Belberith in ''VideoGame/DevilSurvivor'' is a combination of all of the previous Bels that he had absorbed off-screen. He does, however, avert the part of this trope that makes him have more weaknesses, as he's [[ThatOneBoss hideously overpowered]].

[[folder:Web Comics]]
* In ''Webcomic/ElGoonishShive'' a [[VoluntaryShapeshifting shapeshifter]] engaged in the [[MindOverMatter telekinetic]] grapple with a monster [[spoiler:to prevent it from killing her friends]]. Her friend reminded that she passed out after doing this before and urged to switch to "a better form for this" if she can. One bout of panic, instinctive shape change and messy explosion of part of the monster later--
-->'''Sarah:''' Um... uh, what form is this?\\
'''Grace:''' ''(looking at herself)'' ...well... if i had to guess, i'd say... all of them?" [[spoiler:It didn't include all her ''innate'' forms yet.]]
** After this point Grace could engage in this with any or all of her forms on a whim. The results are referred to as Legion Forms.
* Can happen by default if a shapechanger has a miscast in ''Webcomic/{{Runewriters}}''. A good example is Severian, who at the start of the series is stuck with a set of horns no matter what animal he is. This later is added onto after a miscast gives him [[spoiler:tentacle hands]].
* The rings and scepters of ''Webcomic/{{Homestuck}}'' royalty grant their bearers aspects of each of the sprite prototypings. While this makes the royalty progressively more powerful as more prototypings are added, it also makes their appearance progressively more bizarre.
* This is what changelings look like mid change in ''Webcomic/CharbyTheVampirate'', a nightmarish mishmash of limbs, tails and teeth as well as the [[spoiler:struggling dissolving form of whatever or whomever they are changing into as it is absorbed into the mess]].

[[folder:Western Animation]]
* Kevin of ''WesternAnimation/{{Ben 10}}'' turns into one of those in the episode "Framed". During it, he has all the transformations Ben has due to draining energy from the Omnitrix in the previous season, ''and'' he can do PartialTransformation. After taking enough damage and after an insult, he's [[ShapeshifterModeLock locked in said mashup form.]] The result is a conglomerate of all ten forms and his own hair...
** Later in ''Ultimate Alien,'' Ultimate Kevin is a mashup of the ''new'' aliens.
** In one of the later arcs of ''Omniverse,'' Kevin's twelve-year-old self (via flashback) and present self experience similar mashups (The twelve-year-old becoming a fusion of young Ben's second ten aliens, and the present one becoming a fusion of ten of Ben's newest aliens).
* {{Invoked|Trope}} in an episode of ''WesternAnimation/BatmanBeyond'', where Terry's facing the genetic engineer responsible for the [[LegoGenetics splicing]] craze, who's injected himself with the DNA of three forms to become an apex predator. Terry then injects him with [[PhlebotinumOverload a whole fistful of syringes]], and... [[BodyHorror hoo boy]].
* Alpha of ''WesternAnimation/MenInBlack: The Series'' is a former human who's taken to tearing parts of various aliens and grafting them to his own body to become [[UltimateLifeform a superior being]]. At his most benign, he's an old man that can sprout about a dozen [[CombatTentacles tentacles]] on a second's notice. At his most [[OneWingedAngel extreme]], it's impossible to tell that the thing you're looking at was ''ever'' a human.
* In one episode of ''WesternAnimation/CareBears'', Beastly is given an amulet that allows him to transform into different creatures. Eventually, the amulet stops working and he is trapped as a MixAndMatchCritter