Classic Big Bads have the tendency, when push comes to shove, to turn into big honking monsters. A Mad Scientist in a fit of urgency might down his own Psycho Serum, or a practitioner of Black Magic might mutate himself into an Eldritch Abomination, or... you get the idea. Bets are good they'll become way more bloated, ugly, or plain disfigured. And with this new form, their power grows immensely.
This indicates that the villain means business and it's time for the heroes to get cracking.
Named in honor of Sephiroth, Final Boss of the video game Final Fantasy VII (okay, named in honor of his Battle Theme Music — he actually has seven wings, but just one in place of an arm). Video games in general absolutely adore having their final boss do this, even when their original form is scary enough anyway. In fact, it's gotten to be somewhat of an arms race: thanks to the popularity of Frieza in 1991, three-form bosses are now somewhat common, and those games going for "epic" will sometimes go for even more. In JRPGs, particularly, it is rather common to see two stages of One-Winged Angel: the "bizarro" form, that is huge and scary, and the "angel" form, that is winged, eerily beautiful and accompanied by Ominous Latin Chanting. Once beaten, or on becoming even more powerful, the villain may cross the Bishōnen Line and into safer territory for an Evil Makeover to work its magic (though it's a case of Tropes Are Not Bad; as much as it's used, you'd be hard pressed to complain when they turn into something completely awesome). Usually accompanied by the stock phrases "No one who's witnessed this form has lived to tell the tale!", "I have only begun to fight!", or "This isn't even my final form!"
Sometimes you never even fight their human form at all and they immediately turn into a monster. Can count as The Unfought if they showed fighting ability in their human form. This is more popular among minor video game villains who will often transform into tougher versions of earlier monsters like in the Breath of Fire and early Final Fantasy games, as a unique battle sprite for them would take up extra development time and storage space on the cartridge (one unique boss could take the space of several mooks, more with the use of a Palette Swap).
Interestingly, heroes, particularly transforming characters, have been known to occasionally use this "turn into a big scary monster" tactic for their Super Modes as well. It's extremely rare for it not to cross into Superpowered Evil Side territory. And for those with firmer morals, this qualifies the villain as a monster, making it fine to kill him.
Scaled Up and Make My Monster Grow are major subtropes. Super Mode is a sister trope. See also Power-Upgrading Deformation, I Am Not Left-Handed. Compare Emergency Transformation, Lovecraftian Superpower, Came Back Wrong, and Not Even Human. Some subversions are to make it a Clipped-Wing Angel or Power Up Letdown. When the transformation is caused by the character's pain or anger it's Hulking Out. For when the transformation is the villain dropping their humanoid disguise and assuming their true, more powerful form, see This Was His True Form.
Before adding examples, please be aware that this trope is not about just transforming into a monster. It's not even about villains who can transform into a monster. It's a plot trope for climactic final battles with villains.
- Anime & Manga
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- Live-Action TV
- Tabletop Games
- Video Games
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- Western Animation
- Magic: The Gathering:
- Cards like Form of the Dragon do this to the player.
- Meanwhile, cards that do this to CREATURES are too many to count. Green in particular can transform even the meekest creatures into game-ending monstrosities. However, on top of it all is Eldrazi Conscription, which apparently can transform any creature into an Eldritch Abomination.
- Can happen in the card game version of Legend of the Five Rings when overlaying a character with an Experienced version of said character that is infected from Shadowlands taint. This can cause normal-looking samurai such as Kuni Yori, Ikoma Ryozu, or Hida Amoro to instantly increase in power while also becoming disfigured monstrosities. Already-monstrous Shadowlands beings such as Moto Tsume and Akuma no Oni become even more horrific-looking as they increase in power. A rare heroic example is Togashi Yokuni whose Experienced 2 artwork shows him finally transforming into his dragon form. In the official fiction, his brother Fu Leng likewise becomes a dragon at this point to battle him. Yokuni doesn't survive. Intentionally.
- Yu-Gi-Oh! also has too many examples to count — probably more than is entirely healthy.
- Legends of Runeterra:
- Ursine Spiritwalker is normally a man wearing bear skins and middling stats for the cost, but if you play him with plunder effect activated, he becomes Stormclaw Ursine, half-man half-bear monster with increased attack and aura granting Overwhelm to your other units.
- Shyvana transforms into her true dragon form when she levels up. It doesn't give her much of an immediate stat boost, instead giving her larger temporary boost when she attacks and providing you with an extra Strafing Strike card to play on that turn. Classic "Witness my true power!" voice line is of course included.
- Renekton and Nasus become towering giants in their level 3 forms, with accompanying increase in statlines to 10/10 (potentially much more in case of Nasus).
- The concert is over. You have just confronted the most sublime manifestation of avant-garde classical music. You survived its tone clusters and polytonality. The thundering dissonance and disharmony begin to fade away from your aural registers — and with that, a new appreciation for sound in all its forms sets in. Out of respect for the sheer artistry of the pianist, you and the rest of your party begin to clap. The pianist, exhausted of his repertoire, walks back out onto the stage to bow to the audie—wait, what. What is he doing? Oh—Oh God. Oh God. He's come back. Oh God. He's returning to the piano.
- A particularly appropriate example — Henry Cowell's Dynamic Motion is considered a rather... out-there piece of avant-garde piano, described as an act of "pianistic violence". This alone would make a suitable BGM for any RPG final boss battle music... Then you have the Four Encores to Dynamic Motion. The fourth, Antinomy, is just asking to depict a scene where a slain alien horror resurrects itself out of its own corpse as a distorted choir sings its glory in the background.
- Michael Jackson pulls this off with great effect in his music video Ghosts as the Maestro. He also does a pretty good Demon Head near the end.
- In Metroid Prime Pinball, this is Metroid Prime in both of its forms, and the second one can only be damaged with a specific powerup.
- After losing a match against Evolution in 2003, the "Big Red Monster," Kane, was forced to permanently remove his trademark red-and-black mask. This resulted in audiences seeing his true face for the first time since the character's debut 6 years earlier - despite allegedly having been severely burned in a fire, Kane's face was not covered in scars as he claimed; he was simply that insane. Now that he could no longer hide his "disfigurement", Kane became even more psychotic and dangerous than before.
- Japanese pro wrestling loves this trope. Jushin "Thunder" Liger, during intense rivalries, sometimes transforms into the more aggressive, much more evil looking "Kishin Liger". Also Bx B Hulk, a normally upbeat gimmick about dancing, turns into "Killer Hulk", adopting an all black costume and evil looking facepaint.
- Mick Foley occasionally treats his Cactus Jack persona as this. In his feud with Triple H, him shedding his Mankind persona to turn into Cactus Jack scared the crap out of Triple H.
- For particularly serious grudge matches, Delirious will don a "Red Poison" variant of his traditional ring attire with a black-and-red color scheme instead of black-and-green.
- NXT's Finn Bálor is definitely so much this when he dons his demonic bodypaint for special events, claiming he's channelling an actual demon through it. It's a callback to his popular paint jobs in his past as Prince Fergal Devitt prior to WWE signing him.
- Aztec Mythology does this all the time. The gods generally have two forms, an attractive one, and other more animalistic or downright bestial!
- Older Than Feudalism with Jesus. No, seriously! In the Book of Revelation, particularly chapter 19, He shows up as a Warrior Prince with flaming eyes, surrounded by Instant Runes and riding a white horse at the head of a legion of angels. He spits a burning sword out of His mouth, summons an army of carrion birds, and proceeds to lay the smack down on the various monsters, demons, and false prophets that had been corrupting the earth and fighting with His forces for the previous couple chapters.
- In The Kalevala, the evil sorceress Louhi turns into the mythical thunder bird Kokko to pursue the heroes, wielding scythes for her claws.
- A lot of Hindu deities have avatars that basically serve this purpose. Kali, in particular, is a terrifying and destructive (but not evil) form the warrior-goddess Durga assumes to deal with the extremely powerful demon Raktavija. It doesn't end well.
- The oft-quoted Robert Oppenheimer describes Vishnu as taking on a "multi-armed form" before making the infamous Badass Boast.
- As a heroic example, in the epic, Táin Bó Cúailnge, Cuchulainn enters a "Ríastrad" or "Warp Spasm". In this state he transforms into a horribly mutilated monster whose very appearance is enough to scare enemies away. The catch is that, while in this form, Cuchulainn may not know friend from foe.
- There's a three-headed dragon in Zoroastrian mythology named Azhi Dahaka, who is said to be one of the worst evils humankind will ever have to deal with. His origins aren't clear in the Avesta, the most iconic story about him is from The Shahnameh which was written thousands of years after the first time the monster was mentioned. The Shahnameh depicts the dragon as a formerly human tyrant with two brain eating snakes on his shoulders who was imprisoned inside a volcano after the revolution that followed his milennia-long rule. Many Iranians like to do a bit of Canon Welding, believing that the Shahnameh's Zahhak has grown and mutated into the dragon form over the years.
- Bill Cosby's wife does this in one of his standup routines when she notices that Bill fed the kids cake for breakfast. Her face splits in half and she gains the ability to shoot fireballs from her eyes. Then she screams "WHERE DID THEY GET CHOCOLATE CAKE FROM!?!?!?!?!?!?!"
"I always heard of people having a conniption. But I never thought I'd see it. You don't want to see them."