Sibling Fusion

Now, that's brotherly bonding.

What's cooler than Fusion Dance? How about a Fusion Dance between siblings.

A Sibling Team is already awesome enough but being able to form one being takes it to a whole new level. This can be a way of expressing just how close the siblings in question are. Some believe that twins share the same soul, so some writers will go as far as having them share the same body.

An involuntary Sibling Fusion can be used to express how unhealthy and dysfunctional the sibling relationship is.

Not to be confused with Two Siblings In One (which involves someone housing the soul or Life Energy of their dead sibling) or My Sibling Will Live Through Me (which has someone assuming the personality or identity of their dead sibling)

See also Wonder Twin Powers and Twin Telepathy.

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Examples:

Advertising

• Respect the Pouch: In the webseries, the twins Bobby and Sue are fused at each others' backs into "Bobbysue" as punishment for stepping on the pouch together.

Anime & Manga

• D.Gray-Man:
  • Twin brothers Jasdero and Devit can shoot each other in the head to merge into one single entity named Jasdevi. While it is hinted that Jasdevi might have split into the twins, they are seen as separate entities in both the manga and anime.
  • Chapter 2 of the Reverse novels (Episodes 33-34 of the anime) has a witch akuma who is actually a pair twin sisters souls fused together. The back story is that the ill twin sister was forced to become the town's witch after the previous one died while the healthier twin left town in order to learn medicine so that she could help her ill sister. When the healthy twin returns, she finds out her sister has died and begs the Millennium Earl to bring her back to life which he does and the healthier twin fuses with her sister resulting in one akuma made up of two people. The sisters then vow revenge on the village for mistreatment to the ill twin. This is rather notable as every other akuma kills the person who brings them back and wears their flesh as their human disguise making the twins a rare exception to the rule.
• DinoZaurs: The Cerazaur Brothers can combine into Dino Triblades.
• Dragon Ball:
  • Dragon Ball Z: The Tree of Might: Among Turles's minions are the twins Lakasei and Rasin, who can merge into a single being and separate at will.
  • Dragon Ball: Yo! Son Goku and His Friends Return!!: Abo and Kado are two alien brothers who served Frieza when he was alive. They can fuse into a being called Aka.
  • Dragon Ball Super: During the Tournament of Power arc, Shin proposes the idea of Androids 17 and 18 fusing together using the Potara Earrings. Beerus acknowledges they would be quite compatible since they are twins and the resulting fusion would be very powerful. However, the idea is discarded after Whis explains that if the fused fighter is ringed out, it would count as both fighters being eliminated, resulting in two losses for their team.
• MegaMan NT Warrior: Cross Fusion allows a NetNavi and their operator to fuse together. As Lan and MegaMan are brothers, they qualify for this trope when they fuse together.
• Naruto: Sakon and Ukon are twins whose kekkai genkei allows them to fuse together by breaking their bodies down on a molecular level.
• One Piece: Charlotte Newshi's Devil Fruit ability (the Gocha Gocha no Mi, or Mix-Mix Fruit) allows him to fuse with his nine decuplet siblings into a giant lanky figure with a Sinister Scythe.
• Teenage Mutant Ninja Turtles: Legend of the Supermutants: The four Turtle brothers can merge into the more powerful Turtle Saint.
• Transformers: Super-God Masterforce: Decepticon Godmasters Buster and Hydra, brothers whose alt-modes are a pair of jets, are able to combine into a single jet known as Darkwings.
• Transformers: Robots in Disguise: Optimus Prime and Ultra Magnus are brothers in this continuity and have the power to combine into Omega Prime. In this form, they are pretty much unstoppable.

Card Games

• Yu-Gi-Oh!: The Ojama Brothers (Ojama Yellow, Ojama Green, and Ojama Black) can be fused into Ojama King.

Comic Books

• Hellboy: Roger the Homonculus' older "brother" (a flawed prototype) spent years building a monstrously huge homunculus body for himself and Roger to Take Over the World. Roger feigns to accept and is swallowed, only to release his power (well, Liz's power he'd accidentally drained from her) to burn up the body and his brother. Roger then returns the power to Liz to save her life, rendering himself inert, but the Bureau gets him a battery that lets him function again.
• Marvel Universe:
  • Generation X: It is revealed in Issue #31 that the Monet St. Croix we've been following is actually a gestalt being created by her younger twin sisters Claudette and Nicole merging together. The twins can also merge with their brother Emplate to form M-Plate.
  • Spider-Man: The Amazing Spider-Man (1963) #208 introduces twin brothers Hubert and Pinky Fusser. Both worked at the same company but in different professions; Hubert was a scientist while Pinky was a janitor. An accident occurs during one of Hubert's experiments causing the two brothers to merge together into a being known as Fusion the Twin Terror.
• Mortal Kombat (Malibu Comics): Sing and Sang (pictured above) are a pair of twins who can merge into a warrior named Siang. Individually, they possess exceptional skills but when merged together their abilities double. Unfortunately, they were no match for Goro, who forced them to defuse, killing Sang in the process.
• Transformers: Optimus Prime: Oiler and Slide are twin siblings who have a shared alt-mode of a fuel truck (Oiler is the front half while Slide is the back half). When Oiler was killed during the Junkion invasion, Slide was left unable to transform and very bitter as Optimus had made peace with the Junkions.

Fan Works

• Godzilla fanfiction Abraxas:
  • Inverted in a sense. San (Ghidorah's left head) fuses himself to the unrelated Dr. Vivienne Graham to make them a two-headed new hybrid Titan. San considers the two of them to be brother and sister by virtue of merging, just as Ghidorah's other two heads were San's "brothers" before San was severed from Ghidorah's body. Vivienne initially rejects San as a brother, but gradually comes to accept him as such as their character development progresses.
  • It's later revealed that Ghidorah was originally three single-headed brothers before they got forcibly fused into their single-bodied, three-headed form in the backstory.
• The Loud House fanfiction The Sponge House: In "Lona Loud", the Loud twins end up fused together because of one of the inventions of their Child Prodigy sister Lisa. They look like Conjoined Twins and even their outfit is a cross between their outfits— Lana's overalls, Lola's sash, one of Lana's shoes, and one of Lola's. At the end of the chapter, all their siblings, plus their parents, become fused with them. They're fine in the next chapter, though.

• Universe Falls: Dipper and Mabel have a fused form.

Films — Live-Action

• RoboGeisha: Yoshie and Kikuyakko are Cyborg assassin sisters. After spending much of the movie as enemies, they join forces, merging together to defeat the main villain.
• Transformers: Revenge of The Fallen: Downplayed with twins Skids and Mudflap. They start the film with this ability, as they combine into an ice-cream truck for their shared alt-mode; however, after returning to the N.E.S.T. base, they each scan a Chevrolet concept car and operate independently for the rest of the film.

Literature

• The Bad Place: In the story's climax, Frank finally kills Candy by teleporting them both all over until they are both Tele-Fragged to death into a Body Horror mishmash.
• Callahan's Crosstime Saloon: The MacDonald brothers pull off a mental version of this in their debut story, as they're essentially one personality in two separate bodies but they didn't start that way.
• Deltora Quest: Steven and Nevets are twin brothers who inhabit one body. Nevets takes over whenever Steven is in danger.
• Thief of Time: This happens to Lobsang Ludd and Jeremy Clockson in the book's climax so they can fix the damage caused by the Glass Clock breaking. It's not too surprising considering the reveal that they were originally one being, but got separated when their mother, the Anthropomorphic Personification of Time, experienced a difficulty during childbirth.

Live-Action TV

• Moone Boy: Martin pictures his schoolyard bullies the Bonner Brothers as a single two-headed giant during an Imagine Spot.
• Power Rangers Dino Fury: The monsters of the week in "Crossed Wires" are the Stone Triplets, a trio of monster siblings. The Rangers destroy one of them earlier in the episode and the remaining two fight the Rangers in order to avenge him, fusing together during the Mech vs. Beast fight.
• Teen Wolf: The twins Aiden and Ethan can meld together to become an enormous werewolf.
• Ultraman R/B: The brothers Ultraman Rosso and Blu can fuse into the super warrior, Ultraman Reube. They first do this in the final episode to defeat Leugocyte and avert the bad destiny where they die at its hands like their predecessors did.
  • Starting from Ultraman R/B The Movie: Select! The Crystal of Bond, Rosso and Blu can also fuse with Ultrawoman Grigio, the Ultrawoman form of the sister of their human hosts, into Ultraman Groob to defeat even stronger opponents.

Myths & Religion

• In Russia, a few plant species which produce different-colored flowers on the same plant are collectively known as John-and-Mary (Иван-да-Марья). The legend behind the name is that two siblings by these names were separated during a Mongol raid and made slaves. After growing up, they met, fell in love and married, but then the relationship was revealed, and they desperately prayed to God that he would allow them to remain together somehow. Hence the flowers.

Tabletop Games

• Warhammer Fantasy: Vilitch the Curseling◊ is an unholy fusion between Vilitch (a scrawny Squishy Wizard) and his twin Thomin (a mighty warrior), created when Vilitch prayed that he would no longer be his brother's victim. Tzeentch answered his prayer, and Vilitch was bonded and given control over his brother's body. Later the situation was reversed, and Thomin was in charge, casting the spells his brother knew.

Video Games

• Brutal Mario has the Koopalings fuse, resulting in an intense RPG-like boss fight.
• Dragon Ball: Fusions: Android 1718 is a fusion of Androids 17 and 18.
• The Legend of Zelda: Ocarina of Time: Koume and Kotake are twin witches and can merge into a single being called Twinrova, who has the combined powers of the two siblings.
• Mega Man Battle Network 6: Cybeast Gregar and Cybeast Falzar: Wily reveals that he had removed Colonel's compassion components and reprogrammed them into a separate NetNavi called Iris, whom he refers to as Colonel's younger sister. He also states that if the two ever merge again, the resulting program will be unstable and spontaneously self-destruct. At the end of the game, Colonel and Iris fuse together in a last-ditch effort to exorcise the Cybeast from MegaMan's body. Though they successfully stop the monster's rampage for good, it comes at the cost of their own lives.
• Mortal Kombat: Armageddon: In Mileena's ending, she defeats Blaze and his energy causes her and Kitana to temporarily fuse together. When they separate, they discover they have swapped features; Mileena now has Kitana's beautiful face, while Kitana has Mileena's Tarkatan teeth. This allows Mileena to pose as Kitana and have her thrown into prison where she goes insane.
• Voltage Fighter Gowcaizer: Twins Ryo and Suzu Asahina fuse together in their Kaizer Form to create the sub-boss Platonic Twins where Ryo becomes the arms, shoulders, legs, and head or Suzu is suspended in the centre as a torso and arms. Despite the boss name having "Platonic", there is also a case of Romantic Fusion at least according to the Original Video Animation adapation.

Webcomics

• Girl Genius: Baron Klaus Wulfenbach is the result of his parents stitching him together from the remains of their three sons after a grisly lab accident. Considering Klaus' success as an adventurer and ruler of Europa, it's hard to argue with the results.
• Shotgun Shuffle: While shopping for toys on Black Friday, Ellie's second-oldest sister Tarragon and her youngest sister Pumpkin randomly fuse together into a being called Pumpagon.

Western Animation

• The Powerpuff Girls (2016): The finale of "Power of Four" has Bliss, Blossom, Bubbles and Buttercup join together into a construct of a bigger Powerpuff Girl to fight HIM.
• Tenko and the Guardians of the Magic: The twins Jana and Jason can fuse into a two-headed dragon form, achieved by placing their personal Starfire (Amber for Jana, Ruby for Jason) gems together.
• Transformers: Animated: Jetfire and Jetstorm are two Autobot brothers who can combine into a gestalt named Safeguard.

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