Every battle, sci-fi or fantasy anime has that scene where a character undergoes some alarming transformation -- one that might baffle or confuse you once it happens. These forms are not necessarily the strongest transformations, but they are shocking -- either due to how bizarre and unusual they are or how monstrous they become.
From Dragon Ball to Akira, final forms have a long and complicated history, often defying expectations in the face of what was before a fairly standard series of transformations. The following forms are the strangest of the lot -- though, be warned: there are spoilers from this point onward.
Tetsuo's Final Form (Akira)
Tetsuo's final form in the last act of Akira is nothing short of legendary nightmare fuel. Throughout the film, we learn that the various psychic children need to receive special treatment to survive. Still, we don't come to understand why until Tetsuo's body starts to undergo a grotesque transformation. His flesh becomes a molten mess of viscera and newly formed appendages as his psychic abilities grow too rapidly for his body to contain.
Nobody, including Tetsuo, seemed prepared for the intense mutation as it becomes a surreal parody of birth. Taking the shape of a grotesque baby, Tetsuo screams out as his body expands out with a mind of its own. The horrifying mass of flesh continues growing, swallowing up and crushing people like bugs -- including Kaori.
Toguro's 100% Form (Yu Yu Hakusho)
Yu Yu Hakusho's Toguro -- specifically, the younger brother -- is a former human who gained the strength of a demon in his journey for power. When we meet Toguro and he first fights Yusuke and Kuwabara, he only uses barely 20 percent of his power. This left audiences asking, what does 100 percent look like? As the Dark Tournament progresses, we see Toguro unleash and reveal more of his capabilities. In the final match between Yusuke & Toguro, we see the former human's full power.
Toguro's muscles expand to bizarre sizes, with his skin becoming encased in a hardened, boney shell. His shoulders and face distort into something alien, almost reminiscent of Gargoyles' Goliath. Many people expected Toguro's final form to look like, well, a bigger version of Toguro. Instead, Toguro's power is so immense that his aura alone can melt the people around him and his entire look revealed his shift from human to a demon.
Overhaul (My Hero Academia)
My Hero Academia's Overhaul is a compelling villain, able to deconstruct or reconstruct anything he touches with his hands. During his battle against Izuku Midoriya, he assimilates two of his allies into his body. After absorbing Nemoto, Overhaul transforms into a strange figure with increased power, but it's his added fusion with the hulking Katsukane which marks his truly nightmarish final form.
The frightening fusion of Overhaul with his goons sees the villain become a hulking monstrosity. As his fight with Midoriya continues, Overhaul constantly tries to reassemble himself -- which occasionally left him looking like a swirling cloud of meat and a half-formed, miniature kaiju. However, one of the most unsettling things about Overhaul's transformation was how his torso emerges from the interwoven sinew of his transformed body, like a Final Fantasy villain in his final form.
Gluttony (Fullmetal Alchemist: The Conqueror of Shamballa)
The original Fullmetal Alchemist series is often dismissed as a weaker counterpart to Fullmetal Alchemist: Brotherhood. However, Fullmetal Alchemist: The Conqueror of Shamballa showcases something the original manga or Brotherhood never did: Gluttony as this behemoth monstrosity. After devouring Dante and consuming the Earth's raw materials, Gluttony reemerges during the film as this hulking, multi-limbed creature.
Gluttony's presence is ultimately that of a quasi-mindless monster who unleashes pure destruction. Unlike his playful and very on-brand gluttonous human form, Gluttony looks like a behemoth destroying everything. What's most shocking isn't just Gluttony's exterior transformation, but also the internal one -- something that started when Dante erased Gluttony's personality at the end of the main series.
Death Phantom (Sailor Moon)
When you encounter someone who looks like a skeleton in a robe who holds a crystal ball, it seems like their final form should be predictable. Sailor Moon's second arc villain, Death Phantom, first appears in the form of "Wiseman," an enigmatic specter who lingers on the outskirts. The original anime never featured Wiseman's true form, but the manga and Sailor Moon Crystal showcased it in full.
It turns out Death Phantom was a criminal who tried to revive evil on Earth before Neo-Queen Serenity banished him to the planet Nemesis, which sits beyond Pluto. While the Black Moon Clan would assemble on the planet, Death Phantom became the planet. Death Phantom's final form is Nemesis, a sentient planet with enough power to eradicate the solar system's past and future iterations. Death Phantom went from looking like a lost Ringwraith from Lord of the Rings to being a more powerful version of Marvel's Ego the Living Planet.
Giant Rei (End of Evangelion)
The entire Neon Genesis Evangelion series has a lot to unpack, and Rei Ayanami's fusion with Lilith in End of Evangelion resulted in something genuinely unpleasant to take in. Rei's transformation is seemingly straightforward, with Lilith's white body growing to planetary sizes while becoming increasingly more Rei-like. From there, she grows massive wings and spreads an AT Field that melts all life on Earth into one collective hive mind.
What makes Giant Naked Rei so shocking is how alien her face looks. She has this unnatural, almost haunting expression on her face -- one of pure zeal. On top of that, the Mass-Produced Evangelions around her start to distort and enter into a trance-like state where they impale themselves with unsettling orgasmic glee. This component of the transformation -- her connection to the world around her -- makes it go from unnerving to downright disturbing, with Giant Naked Rei becoming Lovecraftian horror brought to life.
Goku's Super Saiyan 4 (Dragon Ball GT)
Undeniably, one of the most shocking transformations in anime history is Goku's evolution into a Super Saiyan 4 in Dragon Ball GT. Are you surprised to see this? Most people would argue that Goku's transformation into Super Saiyan was Dragon Ball's most memorable transformation scene, and this is true. However, Goku's final form as a Super Saiyan 4 is shocking for a myriad of reasons.
For one, it was the first non-linear Super Saiyan transformation, requiring a change into a Golden Oozaru first before Goku could gain his furry ape-like body. Plus, it was visually unlike any prior form. In Dragon Ball Z, the Super Saiyan transformations followed a simple formula: bigger golden hair, bigger golden aura. For Super Saiyan 4, Goku's hair remained black, and, while long, his hair was shorter than his Super Saiyan 3 hair. The ape-like features added to the form's alien nature. What was most shocking of all was how it deviated from the pattern, presenting something that, to date, remains unlike anything else in the series.