By the Power of Grayskull

Lots of Phlebotinum is voice activated: Kirk talked to the computer, Michael talked to KITT, Automan talked to Cursor. But there is no place where a voice activation is more universally required than when triggering a Transformation Sequence.

You are, more or less, not allowed to transform to your super-powered alter-ego without ranting some special key-phrase. This phrase may or may not be descriptive, but it should almost certainly be pithy. If your transformation Catch Phrase is lame, you will not be allowed to keep transforming.

In situations where the hero explicitly cannot transform without magic words, rest assured that Easy Amnesia or a silencing attack will rear its ugly head at least once, making the change impossible when needed the most. If the phrase also untransforms the hero, expect him to do this by mistake sometimes. Villains in particular will often be tricked into saying their power-down phrases.

And woe betide anyone who mispronounces the transformation phrase, as horrible, horrifying things may result.

The trope originated with comic-book character Billy Batson, who first used the Catch Phrase "Shazam!" to transform into Captain Marvel in 1940.

For some heroes, the phrase can be omitted when time does not allow, especially if the full Transformation Sequence is omitted. Superheroes who do not go through an explicit Transformation Sequence (Batman, Superman) are exempt.

A common Anime phenomenon, where it may be a form of Calling Your Attacks. In the Japanese dialog of Sentai and Anime, the word "Henshin" -- meaning roughly "change" or "transform" -- is often found in the phrase, and is sometimes the entire phrase.

Differs from In the Name of The Moon in that By The Power Of Grayskull is the activation password for the Applied Phlebotinum, while In the Name of The Moon is a harangue directed at the opposition.

This is the magic Catch Phrase that actually causes or facilitates the transformation. For one that is simply a cool kind of rallying cry or way to get the adrenaline pumping ("Flame On!", for example), see Invocation. When either of these contains (or is) the name of the hero's new form, it's Transformation Name Announcement.

See also: Transformation Trinket

Anime and Manga

 * Yu-Gi-Oh: In the first season of the English dub, Yugi's transformation into the pharaoh is usually precipitated by his shouting the title of the series.
 * The title of the series, Yu-Gi-Oh is one of the pharaoh's titles, which translates to "king of games".
 * Parodied in Yu-Gi-Oh the Abridged Series with various shouts when Yugi transforms, the most memorable of which is "Super Special Awesome Ultra Special Sexy Transformation Sequence GO!"
 * Da-da-da-ta ta-ta! Puberty Power!
 * Also "Wonder Twin Powers Activate! Form of, an Egyptian homosexual!"
 * The Ignition Weapons from Tower of God unleash their powers by a very short version of this trope, e.g.: "Narumada, Ignite!" Getting them to listen to you is often a much more complicated matter.
 * Guyver: Likewise, Sho initiates his transformation by emitting the series title in a long, loud shrill. The live-action Made For TV Movies abbreviate the delivery, making him look a lot cooler. The live-action movies have a different character (American college student Shawn Barker, as opposed to Japanese High School Student Sho Fukamachi). Also, other Guyvers throughout various incarnations of the series have shown a few different ways of activating this. In the 2nd film, the Guyver-Zoanoid transforms by yelling "Bio-Morph." In the 1st animated series, Guyver II (in the Japanese version) didn't need a word at all. Guyver III went from yelling "Guyver" to "Bio-Boost" in later episodes. Guess at the end of the day the word just helps one focus.
 * The 1st transformation of Magical Girl Lyrical Nanoha involved Yuuno making Nanoha repeat a long, complicated speech; however, to his surprise, she's later able to transform by saying only "Raising Heart, set up!"
 * She also starts her spells with "Lyrical Magical!" (hence the title). Or at least she's supposed to... you could probably count on your hands the number of times she actually does so.
 * She does do the full speech again for the final battle of season 1, just to up the drama.
 * In the Japanese version, season one, her activation phrase is "Raging Heart, onegai", meaning that please really is the magic word (onegai means please).
 * Getter Robo, the majordomo of piloted Super Robot anime, used the phrase "Change, Getter X", where X was the number/name of the form to be assumed. The actual change was just assembling the combiner team in a new order. Later on in the series the phrase "Open Get" was used to disconnect the component vehicles.
 * Martian Successor Nadesico's Show Within a Show Gekiganger 3, based heavily on Getter Robo and other shows of its type, uses "Let's Gekiga In!" (based on Voltes V's "Let's Volt In") for all its combination sequences, and "Gekiga Out" to disconnect the vehicles.
 * Each of the Sailor Senshi in Sailor Moon went through several different activation phrases over the course of the series, on the order of one or so a season, as they improved their powers and combat ability. The general formula was "[Planet Name] [Something] Power, Make Up!" The dub dropped the "Make Up" bit. The Dub also mucks around with the names themselves (despite originally being in English) sometimes resulting in made up stuff like "Moon Cosmic Dream Action". One really bad time had the Girls calling the first part of the phrase solo, then all at once calling "Make-Up!" The dub, due to the sheer omission of "Make-Up" resulting in it ending up as "Mars Star Power, Planet Power!"
 * The Sailor Hellblazer Crossover Fanfic spoofs this when John Constantine accidentally sets his Transformation phrase as "bloody friggin' hell."
 * Sailor Jupiter's pre-attack powerup Invocation probably counts. "Guardian Jupiter! Stir up the storm, summon the clouds, send me your lightning! Supreme Thunder!" She drops everything but the attack name later on, though. Though it does appear a few times later, making the attack seem more Bad Ass then normal.
 * If that counts, then this counts: "I call upon the powers of Zeus himself, infuse me with your heavenly thunder, which is actually lightning, but no one seems to notice. Pika-chuuu!"
 * Possible subversion: in Mai-Otome, the Otome's Phlebotinum-based powers require a vocal authorization from the Otome's bonded master before the Otome herself can verbally invoke her Transformation Sequence.
 * Spoofed in One Piece: Franky the carpenter is a Schizo Tech cyborg who activates his powers by shouting "Hentai!" (abnormality) instead of the traditional Toku phrase "Henshin!" (transform). While "hentai" can also mean "metamorphosis", its more common meaning of "weirdo" or "pervert" creates obvious humor, as other characters comment he is a weirdo/pervert for running around in nothing but a speedo and a Hawaiian shirt. However, he doesn't even activate his powers this way, and just likes saying the word.
 * In Futari wa Pretty Cure, Nagisa, at least, is quite surprised to hear herself call out her and Honoka's key phrase ("Dual Aurora Wave") when they begin their first Transformation Sequence. This also happens with their after-transformation speech and their attacks. No explanation of any kind is ever given.
 * This was repeated in the spinoff series Futari wa Pretty Cure Splash Star. This time there was an explanation (although not one that can be extended back to the original series), and as a result Saki and Mai don't really question it later on (whereas Nagisa continued to be confused whenever she and Honoka said "something weird again"). By the way, their phrase was "Dual Spiritual Power".
 * Yes Precure 5 had "Precure metamorphose!" (Between that and the looks of the five girls, there have been accusations of ripping off Tokyo Mew Mew, which also uses "Metamorphose" as its phrase.)
 * Fresh Pretty Cure had "Change! Precure Beat Up!", Heartcatch Pretty Cure had "Pretty Cure, Open My Heart!", Suite Precure had "Let's play! Pretty Cure Modulation!" and Smile Precure had "Pretty Cure! Smile Charge!"
 * Tokyo Mew Mew had "Mew Mew X Metamorphose!", X being the name of their eponymous food (strawberry for Ichigo, pudding for Bu-ling, etc.)
 * The dub changed it to "Power Pendant, Mew-tamorphosis!"
 * Trinity Blood: "Nano-machine Crusnik 02, starting operation at X percent level!". Every time Abel says that, he transforms from a big ditz into an incredibly badass killer.
 * The Empathic Weapons in Bleach need their wielder to say the magic Catch Phrase in order to switch into a more powerful form. The Catch Phrase is unique to each weapon (though always including the weapon's name) and must be learned from the weapon itself. The phrase can range from the short ("Snap", "Shatter", "Dance") to longer ("Reign over the frosted heavens", "Shoot to kill", "Sting all enemies to death") to very long ("Flower wind rage and flower god roar, heavenly wind rage and heavenly demon sneer", "All waves rise now and become my shield, lightning, strike now and become my blade", "All things in the universe turn to ashes"). Characters who have gained the ability to unlock a final, even more powerful form of their swords do so with the single word "Bankai", regardless of the length of phrase required for first release.
 * It's also parodied. Urahara tells Ichigo that the only way to activate some "magic armor" is to yell "TAKE THIS! THE POWER OF JUSTICE! JUSTICE ARMOR! JUSTICE HACHIMAKI! EQUIP!" at the top of his lungs. Ichigo eventually figures out it's useless, but not before humiliating himself. It later shows up as an actually useful item in a filler arc, leading to much outrage from Ichigo.
 * While fighting Starrk, the two with the longest release 'phrases' - Kyoraku and Ukitake - activate the first release simply with the names of their swords and without fanfare (contrast with Stark's rather more showy transformation). Helpful given the potential for such lengthy verses getting interrupted by the Genre Savvy.
 * It's said that once a person reaches Bankai they no longer have to say their release phrase for their Shikai, though for some reason they all seem to say it most of the time anyway.
 * Because (unless you have a dumb one) it is awesome and serves as a Badass Boast with visual aides as your shikai activates. Trying to scare the enemy is the more-or-less explicit reason for all the Explaining Your Power to The Enemy that goes on in this series.
 * Aside from the zanpaktou, there's also kido, which can be unspoken by very high level users, to short phrases, to requiring scrolls to keep track of. Using a kido without the chant weakens it, even for the highest-level users, and when a less skilled user tries, it also increases the chance of the spell failing entirely (and possibly blowing up in the caster's face, as frequently happens with Renji).
 * The arrancar usually go into Resurreccion mode by saying a specific word or phrase followed by the name of their zanpaktou. For example, Starrk says, "Kick about - Los Lobos!", Barragan says, "Rot - Arrogante.", and Nnoitra says, "Pray - Santa Teresa!"
 * This is because the premise of them is that they are Hollows who have been brought closer to shinigami, the opposite of Vizards like Ichigo.
 * The shift from "civilian clothing" to bird suits in Gatchaman was triggered by speaking the phrase, "bird go!" into a special wristband. When the show was brought to America as Battle of the Planets, the phrase was "transmute!" In the G-Force permutation, the phrase was "G-Force, Transform!"
 * "Transmute to Fiery Phoenix!"
 * Ronin Warriors/Yoroiden Samurai Troopers used this to don their armor. Usually, they took a transformation stance, yelled out "Armor of X," and some sort of incantation. For Wildfire, this was Tao Jin("the way of virtue"). The subarmor could be summoned at will, and it was donned before entering battle. Apparently, when not in use, their armors took the form of glass spheres with their corresponding Confucian value(depicted with kanji) inside it.
 * Mahou Sensei Negima: Western mages have personal "key" phrases to say before reciting spells. (For example, Negi's is "Ras tel ma scrir magister") There's also a 'training' key phrase for novice mages who don't have a personal one yet.
 * And Pactio cards, which summon a magical artifact for the user with the activation key "Adeat".
 * Modified in the Karas OAVs, where the transformation sequence is spoken by the hero's handler. (It's also one of the coolest transforms ever, albeit very long.)
 * Wedding Peach had two for each hero, because they each had two transformations.
 * Spoofed in Wedding Peach Abridged with, "Bridal Striptease, Go!"
 * Digimon Frontier's Transformation Sequence was triggered by "Execute! (Spirit/Beast Spirit/Unified Spirit) Evolution!"
 * Digimon Data Squad used "DNA Charge!", then "DNA Full Charge", then "DNA Charge Overdrive".
 * The Digimon Savers versions used "Digi-Soul" instead of "DNA", plus "Digi-soul charge -- overdrive!" for the second evolution, and then "Charge! Digi-Soul Burst!" for the final Mode Change.
 * Digimon Adventure 02 has "Digiarmor energize!"
 * This is done with every Digimon, really. "-Insert Name Here-mon, Digivolve to...!" or "-Insert Name Here-mon, shinka!" in the Japanese version, and so on and so forth with different languages. Or, some variation on the phrase; examples include "DNA Digivolve", "Warp Digivolve", and "Matrix Digivolve", among others. The actual phrase is used to activate evolution by the Digimon themselves; the only time it isn't said is when you have a mute Digimon. In this case, though, someone else may say it for them.
 * Pretty Sammy, the magical girl alter-ego of Tenchi Muyo! character Sasami used two different phrases. When she appeared in the first Tenchi TV series, it was "Jugemu-jugemu Gokōnosurikire, Sammy Davis broiler chicken!" In her subsequent appearances, it was changed to "Pretty Mutation! Magical Recall!" And just once was
 * Magical Angel Creamy Mami: Yuu's transformation required the phrase "Pam puru pim puru parim pompun! Pim puru pam puru parim pompun!"
 * Persia the Magic Fairy says "Perukko Raburin Kurukuru Rinkuru" to turn into her Older Alter Ego.
 * Floral Magician Mary Bell says "Mary Bell's Flower Magic!"
 * In Magical Stage Fancy Lala, Miho transforms into Lala by saying "Toki no kioku ni omoi wo komete, ima, Fancy Lala ni karei naru seichou!" which translates as "Bringing my thoughts into the memory of time, grow now magnificently into Fancy Lala!"
 * Hellsing had Alucard use the phrase "Releasing control art restriction to level (#)..." when he goes from merely terrifying to Horror Incarnate.
 * "Activate interlocks, dynatherms connected, infracells up, megathrusters are go! Let's go Voltron Force!... Form feet and legs!... Form arms and torso/body!... And I'll form... the head!"
 * This doesn't happen exactly in the Japanese version (Golion). Before the lions combine into Golion, they do say "Let's Golion!". However, there is no "Form feet and legs..." part; the sequence itself doesn't have any dialogue except at the end in later episodes when Akira Kogane/Keith shouts "Golion!!".
 * In the Sequel Series Voltron Force, the mode change command "Form [color] center!" was added. The various weapon commands ("Form, Blazing Sword!" and its variants) are somewhere between this and Calling Your Attacks.
 * G Gundam has the protagonist shouting "Rise, Shining Gundam!" whenever he decides to call his Humongous Mecha. It's not quite a transformation sequence, but close enough.
 * Gao Gai Gar: FINAL FUSION!! SYMMETRICAL DOCKING!! MEGA FUSION!! SYSTEM CHANGE!! SANMI ITTAI!!
 * Shinkon Gattai Godannar had "Drive change go," "Volspinner slave on," "Mushin ittai Godiner," and "Change Genesister."
 * Princess Tutu averts this trope, but Princess Tutu Abridged throws one in.
 * Ahiru still has a transformation sequence, but it's all visual, with an allegorical egg of light and the same little dance every time.
 * Punie-chan's activation in Dai Mahou Touge (Magical Witch Punie-Chan) is classic: "Lyrical Tokarev, Kill Them All!"
 * Pilot 1: "Nenshin!"
 * Pilot 2: "Gattai!"
 * Pilot 3: "Go! Aquarion!"
 * In Sekirei, the Sekirei gain power with a kiss and a chant, called a norito. Each Norito is unique to that Sekerei:
 * Musubi - These are the fists of my pledge, crush the catastrophe before my Ashikabi
 * Kazehana - Wind of my pledge, blow away the dark clouds of my sekirei
 * Homura - These are the flames of my pledge, burn the Karma of my Ashikabi
 * Tsukiumi - This is the water of my pledge, purify the evil residing in my Ashikabi
 * Shiina - Decaying streams of my pledge, wither the cross of my Ashikabi.
 * Transformers: This trope is actually almost exclusively present in the Japanese-original series for most of the time in the American-original series, it is simply treated as something like breathing, in that it requires little to make it happen.
 * In Transformers Super God Masterforce, their transformations were always voice-activated, in a straight example of this trope.
 * From Transformers Headmasters: HEAD ON!
 * In Transformers Robots in Disguise, Transformers Armada, Transformers Energon, and Transformers Cybertron, Optimus Prime could achieve a secondary transformation by declaring, "Optimus Prime, super mode!"
 * In episode four of Robots in Disguise, Sky-Byte had his mouth full of the MacGuffin, and was unable to transform because he couldn't say "Sky-Byte, terrorize!" around it.
 * CYBER KEY POWER!!!!!!!!!
 * Brave Command Dagwon Try Dagwon!]]
 * Cardcaptor Sakura: "Oh key that hides the power of the dark. I, Sakura command you under the contract! RELEASE!!!!!!!!!" Since CCS is somewhat of a magical girl parody, it doesn't actually cause HER to transform (that's Tomoyo's job), it just causes the key to transform back into the full-sized wand so she can use it to control the cards.
 * Dites in Chrome Shelled Regios are activated by saying "Restoration!" If the Dite has multiple forms, a number is appended to select the specific form: "Restoration Zero-One!"
 * Za Beasto!
 * In Tengen Toppa Gurren Lagann, Simon calls out the transformation of Cathedral Terra to Supergalaxy Gurren Lagann, while doing a reverse Glasses Pull (or crying tears of blood in The Movie). Viral goes Audience Avatar and responds "I was waiting for these words!" Seconded.
 * AI AMU GODDO! (Other characters opt for latin or actual japanese catchphrases when transforming.)
 * In Kore wa Zombie Desu Ka Ayumu and Haruna transform into a Masou Shoujo their keyword is, Nomobuyo, Oshi, Hashitawa, Dokeda, Gunmicha, De, Ribura."
 * Black*Star in Soul Eater calls out to Tsubaki to get her to change weapon forms.
 * Panty and Stocking have an elaborate chant while powering up their lingerie into ghost-slaying weapons. The full version is used once, and later parodied when it quickly decays into apathetic mumbling. Their demonic nemeses, Scanty and Kneesocks, have their own Power of Grayskull chant.
 * In Super Robot Wars Original Generation Divine Wars the main character, Ryusei Date, shouts out 'Variable Formation' whenever he and his two team mates combine in the Super Robot SRX. It's a homage and a parody of this trope because 'Super Robots always have to have a cool combination battlecry.'
 * In Hyper Speed Gran Doll, Hikaru shouts "Gran Change!" to transform.
 * The girls of Makeruna Makendo say "Ma-ken-do!"
 * In Jewelpet Twinkle the girls transform with 'Twinkle Twinkle Magical Charm Winkle Winkle Jewel Flash' while boys transform with 'Grilla Grilla Magical Charm Winkle Winkle Jewel Flash'. They also begin each spell with Twinkle Twinkle or Grilla Grilla respectively. In a later episode the fact the boys and girls transformation and magical phrases are different becomes a plot point.
 * Tekkaman Blade has "Tek Setter!".

Comics
"''Change, change the form of man.
 * Megaton Man uses the word Overkill to transform into his ridiculously muscled superhero form from his ridiculously muscled alter ego.
 * In The DCU, Jason Blood is changed into Etrigan when a certain poem is read, by him or by someone else. The full version is:

Free the prince forever damned.

Free the might from fleshy mire.

Boil the blood in heart of fire.

Gone, gone the form of man,

Rise the demon Etrigan!''"

"''Gone, oh little man so tame,
 * Often, especially in adaptations, only the two last lines are used. To change back, he recites "Gone, gone, O Etrigan! Resume once more the form of man!"
 * Other versions of the poem have been seen to work. Spoofed at least once by Blood himself, while in a particularly snarky mood:

Arise the demon... Whatsisname?''"


 * Captain Marvel's "Shazam!". Along with Cap, the entire Marvel Family uses this magic transformation word. (Except for Captain Marvel Jr., who uses "Captain Marvel!") The Captain Marvel villain IBAC changes back and forth from his identity by saying his own "super" name, as does Junior's villain Sabbac.
 * DC is constantly messing with them, though. Billy Batson (calling himself simply Marvel) is now the wizard who gives the others their powers, Freddy Freeman (formerly Captain Marvel Jr) is trying to become a superhero named Shazam (who still uses his name to transform, but has thankfully gained the ability to make that optional, so he CAN say his name without transforming now), and, in a fit of nostalgia, Billy Batson/Marvel changed Black Adam's word from Shazam to in an attempt to keep Black Adam from transforming. It didn't take. Black Adam then got rid of the powers himself by transferring them to a powerless Mary, creating Black Mary Marvel. Which went well...
 * A different Captain Marvel (There've been at least half a dozen, if not more, superheroes named Captain Marvel, none of which are related) had as his phrase the word "Split!" This would activate his power... the ability to split his body into pieces, even down to individual fingers. This was, apparently, necessary, but it doesn't make a lot of difference since for obvious reasons it wasn't a very long-lived comic.
 * Marvel Comics Captain Marvel parodied this once. Rick once shouted "Shazam" while switching places with Genis and he didn't understand what was that supposed to mean.
 * Thunder Girl, Big Bang Comics' Captain/Mary Marvel pastiche, had the word "Alakazam!" Her evil Nazi counterparts (who more closely resemble the rest of the Marvel family, with another Mary thrown in for good measure) have "Gotterdammerung!"
 * Golden Age hero Johnny Quick activated his abilities by reciting the formula "3X2(9YZ)4A". His daughter Jesse Quick did the same, until she lost her powers. It's not enough just to say the formula: you need to understand the four-dimensional construct it describes, and you also need a certain mental state and/or link to the Speed Force.
 * Towards the end of Johnny Quick's run (pun not intended), other speedsters attempted to point out to him that the formula was really pointless... his powers were simply an ability to tap into the Speed Force. This proved true when, in the process of his  he started his formula several times, then finally simply thought "The hell with it" and ran at superspeed without using it.
 * Perhaps ironically, an even later issue of The Flash had our hero Wally West spouting the equation out of desperation to be faster during a particularly large disaster.  'Pointless' indeed.
 * Johnny Thunder commanded his magical (though literal-minded) genie through the mystical phrase "cei-u". In his early issues the running gag was that he wasn't aware of this, and the magic would happen at seemingly random times without him realizing that it was always after he has spoken the words "Say, you". Needless to say, he wasn't portrayed as very bright.
 * And then, to cue the amnesia part, he got Alzheimer's. He got better. Those magical genies are tricky.
 * Due to a later Retcon, both "cei-u" and "say you" were revealed as backwards misspellings of the genie's name: Yz. Turns out he was a fifth dimensional entity, like Mr. Mxyzptlk and Bat-Mite. Legacy Character Jakeem Thunder's genie is named Lkz, or as Jakeem pronounces it backwards, "So cool".
 * Parodied in Defenders Indefensible, when a shockingly calm Bruce Banner attempts to stimulate a change into the Hulk, with such gems as "Hulk On!" and "Shazulk."
 * The early Captain Marvel knockoff Marvelman, better known now as Miracleman, used the transformation phrase "kimota". (Spell it backwards.) His sidekicks use the phrase "Miracleman". Alan Moore's Miracleman series used both the amnesia and trick power-down cliches.
 * The aliens who pioneered the technology have multiple bodies, and swap bodies by using power words. The mad scientist who plundered the alien technology to create Miracleman put in a few little tricks. For example, when Miracleman hears a particular magic word, he transforms back into a human, and can't change for an hour.
 * The magician Zatanna and her father Zatara speak their spells backwards. (Remember: words backwards, sentences forwards!) However, Zatanna has sometimes explained away the need to do this as being merely a focus exercise.
 * The first Blue Beetle would shout "Khaji da!" and thus cause his Scarab to activate his powers.
 * There's a reason for this:, a point revealed in Blue Beetle #25 (of the most recent series).
 * General Glory, also from The DCU. He forgot his magic catch phrase after being mindwiped by the government. He finally tracked it down via the propaganda comics the government used to issue so they could deny his very existence. "You saw General Glory beating up a tank? Sure... stop reading so much, soldier."
 * A similar situation occurred with Wildstorm Captain Marvel Expy Maximum Man, whose alter ego, Kyle Trueblood developed Alzheimer's and afterwards spent every waking minute saying every word in every dictionary in every language he could find.  it was: Hecatean.
 * Golden Age (now Public Domain) superhero the Green Lama used as his transformation phrase the mantra "Om Mani Padme Hum". Since the Lama was supposed to be Buddhist this makes a sort of sense.
 * Marvel heroine Go Go Tomago transforms into her powered form by saying her own superhero name.
 * The Great Ten's Thundermind uses the mantra "All hail the jewel in the lotus" (or its translation "Om mani padme hum") to transform into the mighty superhero. Since Thundermind is a Buddhist-based superhero, it makes some sense (as with the Green Lama).
 * Hawk and Dove, from the DC Universe, would magically gain their superpowers and costumes by shouting out loud their super-hero names. This would only work if there was danger afoot, however.
 * Kid Eternity, from both Captain Marvel and Teen Titans, could say "Eternity" to summon a historical or mythological hero, who would then disappear after a certain amount of time. His archenemy, Master Man, could say "Stygia" to summon a historical or mythological villain, who would then disappear after a certain amount of time.
 * Issue #24 of Plop! contained a story called "The Bella Button Caper", in which the titular character was legislating to ban all comic books forever. In response, the "Great Comic Book Spirit" gave a twelve-year-old called "Comic Book" Mc Fiend the power to turn into a different DC superhero by saying - what else - "Plop!". After he finally cornered a remorseful Bella, the spirit told her to say "DC", which turned her into a comic book.
 * The trope was parodied in issue #23 of the Stephanie Brown Batgirl series, where she confronts the Reapers, the (Somewhat pathetic, although admittedly dangerous) villains she has faced for the majority of the tail-end of the series. When she finds herself outmatched by the numerically superior Reapers, she shouts Shazam! at the top of her lungs. The Reapers pause momentarily in confusion, and question one another on if Batgirl is magic or not, before the Teen Titans burst to the rescue, having been waiting for the signal to come charging in. They proceed to effortlessly annhilate the Reapers, some of whom do not even bother to look at the Reapers as they defeat them.

Film

 * Hal Jordan attempted to activate his ring for the first time by reciting various catch phrases, eventually progressing to "To infinity and beyond!" and, ultimately, "By The Power Of Grayskull" itself.

Literature

 * The Lathe of Heaven has Doctor Haber use hypnosis so that George Orr will begin his "magic" dream state whenever Haber says "Antwerp".
 * Averted in the Tortall universe, in which the most powerful shapeshifter in the world quite frequently shifts into something else without saying anything at all.
 * After her series ends, she gets pregnant with a baby shapeshifter, and has to change shape whenever the baby does so she doesn't kick her way out. Another character comments that it is quite distracting to try to talk to the shapeshifter when she has to change shape every few minutes.
 * Harry Dresden casts his spells using Latin... ish phrases. He justifies this in his narration by explaining that words in foreign, unfamiliar languages provide a sort of insulation from the raw power of a spell for a wizard's mind. One time in Fool Moon he cast a spell when he couldn't speak. The spell worked fine, but he was badly disoriented for some time after. Presumably if Harry ever worked on his Latin he would have to start casting spells with another, even more obscure language, like most wizards do.
 * In a story by Wilhelm Hauff, the hero and his friend use the magic word "Mutabor" to turn into birds - and promptly forget how to turn back.
 * In Anthony Boucher's story "The Compleat Werewolf", the magic word "Absarka" transformed the main character into and out of his werewolf form. There were just two problems with this: (a) as a werewolf, he had to get somebody else to say the word for him and (b) when he changed back into a human, he was naked.
 * In Bruce Coville's The Monster's Ring, the main character had to recite some doggerel in order to make the titular ring work, one verse to turn into a monster and another to change back.
 * In Zilpha Keatley Snyder's Black & Blue Magic, the main character had to recite a flying-related verse while rubbing a certain magic oil into his shoulder blades in order to grow wings.

Live Action TV

 * Captain Power and The Soldiers of The Future: Members of the Future Force transformed into armored form by calling, "Power on!"
 * 1970s Wonder Woman rip-off Isis forced the titular character to recite a full-sentence incantation to activate her powers. Also, she apparently had to activate powers in a certain order (i.e. she couldn't skip around on her spell list) or an incantation wouldn't work.
 * Thankfully, not so much when she entered The DCU.
 * Family Matters: Urkel would transform into one of his alter egos -- Stefan Urquelle, Bruce Lee Urkel or Elvis Urkel -- by pouring a special potion into one of the tubes attached to the machine; after walking inside, one of his friends would flip a switch to activate the machine and begin the transformation process (complete with bells, whistles and funny sounds that always seemed to elict a laugh). Urkel's trademark voice, clumsiness and physical awkwardness, weird food likes and personal traits, etc., always disappeared when Urkel's alter ego emerged.
 * The machine worked in reverse, often to switch Urkel's alter-ego back to his nerdy self, but several times, it was used -- always accidentally -- to transform Carl and Eddie into clumsy likenesses of Urkel.
 * Every Power Rangers series. Ever.
 * Although in Power Rangers Operation Overdrive there were double-figure instant morphs. Still needed words for everything else, but when there was emotion involved, woohoo baby, they went for the silent approach.
 * They weren't afraid to spoof it from time to time. Whenever Billy did the call, he would often say it in technobabble, i.e. "It's time for molecular transmutation!"
 * It is not entirely clear in which cases the phrase is By the Power of Grayskull, and in which it is an Invocation. For the original rangers, saying the name of their respective animal was required (Zordon tells them to summon their powers thus), and the now-famous prelude, "It's morphing time!" was absent in the very first morph (Zordon is the first to use the phrase in the second episode). With every team since (except Zeo), it was the team call, not the individual call, that triggered the morph. Power Rangers Time Force is a strange case: the Quantum Ranger's morpher was voice-activated, and this is explicitly different from the way the Time Force morphers worked. Doesn't stop them from saying "Time for Time Force!" to morph.
 * Power Rangers RPM justifies the catchphrase as a voice lock for the morphers.
 * Other series have it weird, for example those Rangers (like Power Rangers in Space and Power Rangers Lightspeed Rescue) whose morpher has a password keypad and is used as such, still have team call (and intricate hand gestures before typing their codes).
 * Power Rangers in Space completely skipped the morphing sequence and the catchphrase in "Countdown To Destruction Part 2".
 * And just for fun, let's list them all in order!
 * "It's Morphin' Time!" (Mighty Morphin Power Rangers and Power Rangers ZEO. Then followed with their original dinosaur/animal symbol (for Mighty Morphin Season 1 to 2) or '(insert color here) Ranger Power' (for Season 3) or Ranger designation (for Zeo)).
 * "Shift Into Turbo!" (Power Rangers Turbo)
 * "Let's Rocket!" (Power Rangers in Space)
 * "Go! Galactic!" and "Magna Power!" (Power Rangers Lost Galaxy)
 * "Lightspeed! Rescue!" and "Titanium Power!" (Power Rangers Lightspeed Rescue)
 * "Time For...Time Force!" and "Quantum Power!" (Power Rangers Time Force)
 * "Wild Access!" (Power Rangers Wild Force)
 * "Ninja/Thunder/Samurai Storm! Ranger Form! (Power Rangers Ninja Storm)
 * "Dino Thunder! Power up! Ha!" and "White Ranger! Dino Power! (Power Rangers Dino Thunder)
 * "SPD! Emergency!" (Power Rangers SPD)
 * "Magical Source! Mystic Force!" (Power Rangers Mystic Force)
 * "Overdrive! Accelerate!" (Power Rangers Operation Overdrive)
 * "Jungle Beast! Spirit Unleashed!" (Power Rangers Jungle Fury)
 * "RPM! Get In Gear!" (Power Rangers RPM)
 * "Go Go Samurai!" (Power Rangers Samurai)
 * Head Desk.
 * VR Troopers: used the phrase "(Trooper Transform!) We! Are! V!R!" to initiate their transformations. It's the "Trooper Transform" that's actually needed for the change.
 * Their foe, Karl Ziktor/Grimlord, did this as well, straddling the line between this trope and Invocation: "Forces of darkness, empower me! Take me back to my Virtual Reality!"
 * Big Bad Beetleborgs: "Beetle-Bonders! Beetle-Blast!" (Cue Theme Music Power Up.). "Back-Blast!" reverted them to human.
 * The Metallix season had: "Data-Bonders! Input card! Beetle-Blast!" for their Beetleborg forms and "Bug out!" and "Bug-back" to go to and from their bug forms.
 * The Mystic Knights of Tir Na Nog: "Fire within me!" "Earth beneath me!" "Air above me!" "Water around me!" "Forest before me!"
 * Rohan, The Hero, had Battle Fury Armour, which he activated by shouting... go on, guess.
 * Superhuman Samurai Syber-Squad had "Let's Samurize, Guys!" (for Sam, The Hero), "Let's kick some Giga-butt!" (for Tanker, The Big Guy), "Pump up the Power!" (for Sydney, The Smart Girl), and a random non sequitur (for Amp, the Plucky Comic Relief) that essentially lampshaded the whole pointlessness of the henshin phrases (at least, until he was replaced: Lucky London, the second comic-relief guy, just said "Surf's up!")
 * In the episode where everyone's personalities changed, Tanker and Sydney actually switched phrases.
 * Kamen Riders traditionally use "Henshin", though Showa-era Riders would occasionally use variants, such as Kamen Rider Stronger's "Henshin Stronger".
 * The two Kamen Rider productions to completely avoid this trope are the Deconstruction film Shin Kamen Rider Prologue (whose protagonist bore more similiarity to The Incredible Hulk than a typical Rider), and Kamen Rider Hibiki (except for some goof-ups slipping by Kamen Rider Decade's endgame).
 * Kamen Rider X said "Setup!" instead of "Henshin!" for most of his series, and switched to "Dai Henshin!" towards the end.
 * Kamen Rider Amazon did not say "Henshin" but rather "AAAAAAAA-MAAAAAAAAA-ZOOOOONNNNNN!!!"
 * The Henshin belts for Heisei era Riders sometimes contibute their own phrases to accompany this:
 * "Standing by... Complete."
 * "Turn Up"/"Open Up."
 * "Henshin!"/"Cast off! Change Beetle!"
 * "Sword Form"/"Rod Form"/"Ax Form"/"Gun Form"/"Climax Form"/"Liner Form"
 * "Re-a-dy! Fi-st On!"
 * "Kamen Ride... Decade!"
 * "Cyclone! Joker! CycloneJoker!"
 * "Taka! Tora! Batta! Ta-To-Ba, TaToBa TATOBA!"
 * "Three... Two... One..."
 * The English versions gave us--
 * "Ecto-Phase Activate!"
 * "Kamen Rider!"
 * Madan Senki Ryukendo has the protagonists shout out the name of their Empathic Weapon to turn them from a portable form into full-sized weapons. Since this is Ryukendo, it was Lampshaded in one episode where Kenji is in a large, echoey cave with some civilians a little way down another passage and a Secret Identity to maintain. He tries to whisper the name and his weapon retorts, "Can't hear you."
 * The Chou Sei Shin Series series used "Souchaku!" ("Equip!") as their standard transformation phrase. Chou Sei Kantai Sazer X, in keeping with their Xtremely Kool Letterz, would upgrade this to "X Souchaku!"
 * Tomica Hero Rescue Force, which is actually a Spiritual Successor to Madan Senki Ryukendo, used "Chakusou!" This is the exact same word as "souchaku".
 * In Cutey Honey the Live, Honey transforms by touching two fingers to a little heart charm on her neck and calling "Honey Flash!". Her transformation is a naked/sparkle scene a la Sailor Moon, but the catch is that the people around her can see her naked and sparkling.
 * Super Sentai, the show Power Rangers get their basic concept from. For most of the earlier series that used it, the transformation call was simply the name of the team or form, but later series started to switch it up a bit. Most of these phrases are also used along with some action done with the Transformation Trinket. (Feel free to fill in the phrases of missing series.)
 * "Go!"
 * "Fever!"
 * "Denzi Spark!"
 * "Let's Change!" Or, alternatively, "Change [animal]!" if just one is changing, or if they're feeling particularly dramatic. However, sometimes, the "Let's Change" is omitted.
 * "Prism Flash!".
 * "Aura Mask!"
 * "Cross Changer!"
 * "Dino Buckler!"
 * "Kiryoku Tenshin! Aura Changer!"
 * "Super Henge! Doron Changer!"
 * "Chouriki Henshin!"
 * "Gekisou! Accel Changer!"
 * "Install! Megaranger!"
 * "Ginga Tensei!"
 * "Chakusou!"
 * "Chrono Changer!"
 * "Gao Access!"
 * "Ninpuu / Jinrai / Tenkuu! Shinobi Change!"
 * "Bakuryuu Change! HA!" (Mikoto, on the other hand, doesn't do the last "HA!")
 * "Emergency: Dekaranger!" for the core five. Other Rangers got to personalise it: "Emergency: Dekabreak / Dekamaster", etc.
 * "Heavenly Saints, grant us the power of magic! Mahou Henshin! Maagi Magi Magiiro!" / "Mahou Henshin! Goolu Golu Goldiiro!"
 * "Boukenger! Start up!" / "Go Go Changer! Start up!"
 * "Boil!/Echo!/Sharpen! Power/Cry/Blade of the Beast! Beast on!" (Power Trio gets the first, violet gets the second, white gets the third.)
 * "Change soul, set! Let's Go On!"
 * "Ippitsu Soujou!" / "Ikkan Kenjou!"
 * "Change card, tensou!" (Tensou is used when activating any Gosei Card power, not just the transformation into Goseiger.)
 * "Gokai Change!"
 * "Let's Morphin'."
 * Seiun Kamen Machineman: "DOLPHIN!!!"
 * Ultra Seven: "Dua!"
 * Ultraman Ace: "Ring Touch!"
 * Ultraman Leo: "Reo!"
 * Ultraman Eighty: "Eitii!"
 * Ultraman Mebius:"Mebiusu!"

Tabletop Games

 * Done quite a lot in most RPGs that involve magic. Incantations and the like.
 * Most tabletop games don't require the player to chant anything, as it's assumed the PC says whatever he needs to say to get the desired spell activated (ie, Power Word Kill doesn't specify the word used).
 * Actually, the majority of the incantation is done during the prepariation step. The actions they take to unleash it are simply finishing the last part of the spell. (Sorcerer's use the words to help them focus as their power is largely instinctive).
 * Subverted in Dungeons & Dragons 3.5 edition, as a player can take Silent Spell as a feat, allowing one to cast spells without speaking when speaking is usually require, at the cost of a higher level spell slot.
 * There's also the Nonverbal Spell feat in one of the supplements which allows a spellcaster to bypass the use of words as long as they use some other sound (grunting, mumbling, or even singing). This was initially so that one race which didn't speak could still become a spellcaster. It also allows for a cheaper way of being stealthy than Silent Spell since it doesn't affect the spell slot level.
 * However, GURPS has an optional rule for spellcasting using cantrips; you can prepare in advance (or invent on the spot) a poem to cast a spell; longer poems give better effects. The player, not the PC, must recite or read the actual cantrip, and you're not allowed to "stop time" to make up a poem, so you'd better be good at improvisation or have a prewritten one at the ready.
 * Spells in Kobolds Ate My Baby require the player to perform the correct action/speak the correct words. The phrase for casting "Wall of Beer" was "Tappa tappa kegga, wall o'Beer omega!". Being invisible required the player to cross their arms and do their best to look like a brooding vampire.
 * Explained away in a Shadowrun book. People in the Shadowrun-verse yell, wave their hands in elegant motions, point, say things quite dramatically, and other magicky stuff, but when asked this, a mage says that it's all used to help focus mana. It's not necessary, though.

Video Games
"Geo: Man, that's so embarrassing! I even yelled and everything!
 * The main character of Viewtiful Joe shouts "Henshin-a-go-go, baby!" (sometimes "Henshin around!") to activate his powers and costume because he uses a voice-activated watch. (He only needs to say "Henshin" - but what fun is that?) Similarly, in the same game, Captain Blue and Sexy Silvia also shout "Henshin!", while Stylish Alastor shouts "Devil Trigger!" and "Trigger me, baby!" In Viewtiful Joe 2, Silvia also shouts "Henshin-a-go-go, baby!"
 * In the anime adaptation, when Captain Blue Jr. eventually gains his own powers, he uses a variant of the phrase, saying "Henshin-a-Yo-Yo, baby!" (since he uses yo-yo's as weapons in his transformed state).
 * The main villain of the sequel,, uses "TENSHIN!"
 * Averted in Devil May Cry: Although Vergil says some snappy phrases before using his Devil Trigger power and starting a powerful move, it is unnecessary, as using the Devil Trigger sans said powerful move is accomplished wordlessly. Dante and the playable incarnation of Vergil deliver no lines as they use their own Devil Triggers, either.
 * Dante in the Playstation 2 version of Viewtiful Joe however...
 * Highlight for proof that Dante wouldn't know a cool transformation phrase if it hit him in the face with a large trout: Fortunately, he usually shortens it to the first three words.
 * Kermit's nephew Robin in Muppet Monster Adventure can turn into monsters after collecting their amulets and get their powers, and has a different call for each one.
 * Some of the Lumas in Super Mario Galaxy transform into various objects when fed enough star bits by the player. When this happens, they shout 'Transform!!!' which appears on the screen in a speech bubble in a very large, bold font.
 * And they appear to shout something that sounds like "Henshiiin!"
 * "MEGAMERGE!/ROCK ON!"
 * In the same vein, in order to Wave Change in Mega Man Star Force, one has to first say, "EM Wave Change, (Name), On The Air!"
 * Subverted, then lampshaded by Omega-Xis in the third game when Geo attempts to Wave Change and fails to before being registered with project Trans Code.

Omega-Xis: That's strange, yelling makes everything work!"

"Sumio: A mystery is concealed within this man! An endless journey -- The prey protects its soul -- While the hunter hunts the truth. A requiem solely sung for the search! Truth is singular. It's time to go to work, Catherine! The search culminates here!"
 * The asari of Mass Effect always say, "Open your mind, embrace eternity!" before using their mind-melding powers. It's never addressed whether or not this is actually necessary.
 * Nope, it's just a religious thing. When Liara shares all of her memories with Shepard in Mass Effect 3, she doesn't say it.
 * Done with the "Gun del Sol" from the Boktai series. Django charges it by raising the gun sky-ward and shouting "TAIYOH!!"
 * The Gun del Sol also appears in Metal Gear Solid 4, where it is given the less Spanglish name of "Solar Gun" and Snake now charges it by yelling "sunlight!" instead of "taiyō" (unless you're playing the Japanese version, in that case he will still yell "taiyō").
 * In Flower, Sun, and Rain, Sumio Mondo has a computer named KATHARINE (Catherine in the English), which he activates with a variety of codephrases. Here is the first one:


 * The girls in Arcana Heart all call their Arcana with such a phrase. The biggest standout being Kira's "don't ask why, just give me your powers."
 * Super Monkey Ball 2 and it's quite bizarre story mode where the heroes had to chant a song before they could go rolling around a level. According to the subtitles, the song had lyrics, but it all sounded like "Uki uki uki-ki-ki!"
 * Combined with a Badass Creed in Princess Waltz: A sword in my hand. A vow on my finger. I am clad in white. I will become a contestant in the Waltz.
 * In Blazblue: Continuum Shift when Ragna  activates his Azure Grimoire (thus turning into his Unlimited form) he shouts "Restriction 666 released! Dimensional interface force field deployed. Code S.O.L. Blazblue activate!"

Web Animation
"Bubs: Why are you trying to get me to say Sbu?
 * Spoofed on Homestar Runner with the Strong Bad E-mail "lunch special", in which Strong Bad thinks that getting Bubs to say his name backwards without the first B (in other words, "sbu") will make him give away a free lunch special. Eventually, Bubs says it, and reveals that it doesn't make him give away a free lunch special but rather makes him lose his ability to fly (though he could really only hover a few inches above the ground anyway).

Strong Bad: THERE! You said it! Now you gotta give me a free lunch special!

Bubs: No, no, no. Getting me to say my name backwards minus the B just makes me lose my super power!

Strong Bad: What super power?

Bubs: Being able to fly.

Strong Bad: You can fly!?

Bubs: Well... not anymore, I can't.

Strong Bad: Oh, right."

""Shapeshift unto... a Sumatran tiger!" *DWAYNE!*"
 * The email "shapeshifting" pokes fun at this, with Strong Bad imagining himself gaining the ability to shapeshift and, in addition to having to put up with pointless rules and restrictions, having to activate the power out loud:

Web Comics
"Alina: Probability distribution of... electron cloud!
 * Dresden Codak has the Tokamak twins, not related to the Wonder Twins, and SCIENCE.

Dmitri: Density with mass reaching boundaries of... the Chandrasekhar limit!"

"Ellen: Damn. I was hoping they'd get bigger.
 * In Cheer, Jo tries to activate the mysterious (and thus far useless) wand she's found via Grayskull phrases, similar to Peter Parker trying to use his weblines in the first Spider-Man movie. She even starts to try the original, but doesn't get to finish.
 * Parodied in Tales of Mynarski Forest; when the delusional Heywood raises his "magic sword" to the sky with a call of "By the Powers of Numbskull!" he gets struck by lightning with predictable results.
 * Played with in one El Goonish Shive filler comic: Ellen, having nicknamed her boobs "The Wonder Twins", yells "Wonder Twin powers... ACTIVATE!"

Grace: Are you wearing a towel as a cape?"


 * In Sluggy Freelance, Zoe's transformation powers are enacted by the words "shupid" and "kwi". However, this works whether said by her or somebody else. (Kind of has to, since her alternate form is that of a camel... which can't talk.)
 * In WCI High, plain-looking Blossom Pearl transforms into sexy Awesome Girl by using her magic word, which is actually "MAGIC WORD",
 * Pv P featured a comic about the minor random character Lolbat, who is shown to be a child who activates the power of ancient memes with the phrase, "It's Peanut Butter Jelly Time!"
 * Averted in Order of the Stick: while V does say "Shapechange" before transforming into  for the first time, this is not what actually triggers the transformation. Rather, virtually all spellcasting in OotS has the name of the spell as a verbal component. The next time V transforms, no verbal statement is necessary, as the Shapechange spell's duration has not expired.
 * Xkcd: CAREBEARSTARE!
 * At one point in Bad Guy High, one of the kids got a He-Man-esque suit and a bunch of powers from some magic hermit. To call his powers, he had to call the hermit's name and a lightning would strike him, changing him. Saying it again restored his form, so he made that mistake a couple times.
 * In Emergency Exit, Karl Tameron activates his couch robot by saying the phrase, "I sing the body electric," the beginning of a Walt Whitman poem. While this is not an example, it happens that later that same phrase not only transforms his couch but also seems to give him some manner of super powered electronics control, which satisfies the criteria. Fridge logic dictates that it's possible that he would have gained the super powers if he had a face the first time he said it and didn't need to use the speaking program from the portal bracelet, as he did not say the words himself that time.
 * Sinfest remembers the grayskull. Being performed Seymour, this didn't work well.

Web Original

 * Possibly in a reference to Power Rangers, the Dimensional Guardians from the web fiction serial Dimension Heroes must shout "Dimensional Guardians, power up!" to activate their Guardian powers.
 * Whateley Universe example: When Action Girl Chaka gets a set of magical gloves that - once invoked - let her make four extra-hard punches, she has to choose the invocation phrase. Being a wacky teenager in a superhero world, she chose "It's clobberin' time!".
 * "INTERNET REVIEWER!"
 * Super-speedster Jenny Thunder, a hero from the Global Guardians PBEM Universe activated her speed powers by yelling out the phrase "THUNDERBOLT POWER NOW!"
 * He-Man and The Masters of The Universe and She-Ra doing this was mocked mercilessly by The Nostalgia Chick: "By the honor of pep-talks!"
 * BY THE POWER OF GAYSKULL!
 * "Black Power, motherfucker!" "Deep penetration!" "King Chili, motherfucker! Yeah~!" "Fried rice!" "Jose Canseco!" "Dragon shit!"

Western Animation
"Arthur: I am King Arthur.
 * This trope takes its title from He-Man and The Masters of The Universe, where that Catch Phrase changed unassuming Prince Adam into his titular alter-ego. The much less known power-down phrase (used once each in the 1980's series and the 2003 series) is "Let the power return!"
 * Ironically (since he's the Trope Namer), it's not just the phrase that transforms him, he needs to be holding his magic sword (which he pulls out of Hammerspace). At one episode where he ventures to Orko's planet, where everything seems to work backwards (eg Orko's magic works correctly, and Adam's flame-throwing wrist gun spits out water instead), he had to recite the whole phrase in backwards to transform (he didn't transform when he said the phrase as normal early in the episode, then figured it out after some observing and analysis).
 * He-Man's Distaff Counterpart (and Separated At Birth twin sister), She-Ra, used a minor variant beginning, "For the honor of Grayskull..." In an episode when Adora (She-Ra's alter-ego) is rendered unable to speak, she cannot transform and is powerless until she recovers her voice. In another episode she is also rendered unable to transform when the orb on her sword is cracked by a powerful beam attack from the Horde (fortunately she gets it repaired after performing several difficult labors that test her resolve).
 * Transformers: Possible stretch, but when time permits, conversion to robot mode is accompanied by a transformer calling its own name, then saying, "Transform!"
 * Beast Wars used this trope more extensively, with "Insert Name Here, Maximize!" for Maximals, "Insert Name Here, Terrorize!" for Predacons and "Beast Mode!" for reversing it. Later in Beast Wars, some had vehicular modes with specialized names (at least once, Rattrap called his "Knieval Mode").
 * Specifically, this was required as a voice command in Beast Wars as a trade off for the much smaller, more power efficient bodies than their predecessors (i.e. G1 Transformers which were around three times larger). Another aspect was that the entire procedure was handled by a secondary computer, which also handled other processes such as notififying the individual about low power, exposure to hazardous materials, etc.
 * Actually, it wasn't required. The voice commands existed in the first place because Hasbro wanted viewers to be absolutely sure which character was which. The voice commands were extremely prevalent in Season 1, though were toned down by the end and almost never heard in 2 & 3 unless a new character appeared.
 * In Beast Wars, Dinobot specifically changed his code whenever he switched sides.
 * "I Am Transformed" for the Beast Machines Maximals (a plot point in the early episodes, as the characters needed to learn how to transform, as it had previously been handled by an onboard computer in them.).
 * The Centurions had the activation phrase, "Power-X-Treme!" (or rather "pow-ER ext-REEM!") to beam down their weapons.
 * Captain Planet and The Planeteers: "Let our powers combine! Earth!"
 * "Fire!"
 * "Wind!"
 * "Water!"
 * "Heart!"
 * "By your powers combined, I am Captain Planet!"
 * And when the good deed has been done : "Remember Planeteers, The Power is Yours." to be the powers uncombined, though the first part was optional.
 * It wasn't just necessary for the combination, either. To even use their powers individually, they first had to call out the name of their power.
 * "EVOLUTION! SURVIVAL! SELECTION! SCIENCE! H-AIIIIGH! (THE MONKEY HAS MY LEG! THE MONKEY HAS MY LEG!!)
 * Super Ted had the phrase "I'll just say my secret magic word..." and then the teddy bear would turn into SuperTed. The word was never revealed (it was hinted that the phrase was itself the magic word, but it was never confirmed), but in one episode, Bulk (one of the "bad guys") overheard it and used it to turn into Super-Bulk. The same episode had SuperTed forget the word himself. This seemed to ignore the fact that Mother Nature hadn't ever given Bulk a magic potion to become super powered...
 * Thundercats' and its reboot ThunderCats (2011) have several:
 * Lion-O's Situational Sword, the Sword of Omens, requires him to say "Thunder! Thunder! Thunder! Thundercats, Ho!" to cause the sword to lengthen from dagger to longsword length unlock its full combat potential and rally the troops to battle with a Bat Signal.
 * A simple "Thundercats, Ho!" or "Ho!" is sometimes sufficient to fire a bolt, temporarily grow the sword, and activate a number of other context-sensitive powers. In the original, Lion-O did occasionally grow the sword without so much as a word.
 * "Sword of Omens, give me Sight Beyond Sight!" allows Lion-O to use the sword's Psychic Powers. This particular example is parodied in the Family Guy movie, where Lion-o uses the sword to spy on Cheetara in the bathroom.
 * In the original, when separated from it, Lion-O could say "Sword of Omens, come to my hand!" to get it back. This even worked over interstellar distances, but he didn't use it as often as he should have.
 * A villainous example: Big Bad Mumm-Ra transforms into a One Winged Angel form with the incantation "Ancient spirits of evil, transform this decayed form, into Mumm-Ra... the Ever-Living! Bwa ha ha ha HA!"
 * In one particularly embarrassing original series moment that that Mumm-Ra will never live down, Snarf of all people takes advantage of this catchphrase to become even more beefy than Mumm-Ra himself. Clearly Mumm-Ra's transformation chamber could do with better security.
 * The sister series Silverhawks also had a villain with a transformation speech: "Moon Star of Limbo! Give me the might! The muscle! The menace! Of MON...STARR!!"
 * Winx Club: Before 4Kids edited it, Bloom says "Bloom Magic Winx!" some of the time before transforming, with the other fairies substituting their names instead. Around season 2, it got reduced to just "Magic Winx!" When the girls earned new outfits, 4Kids did have the girls saying "Go Enchantix!" for a while.
 * Not everyone likes transformation phrases.
 * Possibly similar to Inspector Gadget's "Go, Go, Gadget X!", a phrase that was used to activate the required gadget 80% of the time.
 * You mean the wrong one 80% of the time.
 * The Wonder Twins, from the second season of Super Friends, would shout "Wonder Twin powers, ACTIVATE!" to, well, activate their Wonder Twin Powers. This was followed by Zan shouting, "Form of (something made of water or ice)!" and Jayna shouting, "Shape of (an animal or alien creature)!" (Interestingly, the comics made it clear that this wasn't required at all, but just a habit; presumably as a courtesy to the audience who wouldn't understand that the Twins had just shifted shape.)
 * This habit, and the entire concept of the Wonder Twins, was hilariously subverted in a Cartoon Network promo disguised as an Eighties-vintage "you can do anything you set your mind to" spot: after telling the kiddies they don't need superpowers to be cool, Jayna transformed into a green tiger, and Zan into a bucket of water... whereupon he began lamenting his lame superpower, and exclaimed, "I could be defeated by a sponge. It wouldn't even have to be an evil sponge!" And an evil sponge (you can tell by the eyebrows) leans out from a group of lurking villains.
 * Challenge of the Super Friends added Apache Chief and Samurai as token ethnic characters to their line-up. Apache Chief could grow to 50 feet tall by saying "Inekchok!", which the narrator once assured us was the Apache word for "giant man". Samurai could turn into a tornado by saying "Kazi noyo ni hiyaku!", or turn invisible by saying "Koya ningi!"
 * To H-B's credit, Samurai was using genuine Japanese: "Kaze no yō ni hayaku" means "As swiftly as the wind", and "Tōmei ningen" means "Invisible man". It's entirely possible that Apache Chief's "Inekchok" is linguistically legit too.
 * Apache Chief's power was parodied by Family Guy. Saying "Inekchok" makes Quagmire's penis grow larger!
 * Used by Freakazoid, without even Lampshade Hanging it to any real degree. He has to say "Freak out!" to transform into Freakazoid, and "Freak in" to turn back into mild-mannered nerd Dexter Douglas. When Dexter says "freak out", he always precedes it with an extended "Ah" sound, like the chorus to the disco song "Le Freak" by CHIC.
 * In Fred and Barney Meet The Thing, young Benjy Grimm would transform into The Thing by touching his magical rings together and saying "Thing Ring, Do Your Thing!"
 * Subverted in Duck Tales, where Bungling Inventor Gyro Gearloose programs the Gizmoduck suit to be activated by the phrase "blabbering blatherskite", believing that nobody uses it. Little did he know that it was mild-mannered accountant Fenton Crackshell's favorite expression and that he would transform into Gizmoduck for the first time purely by accident after uttering this phrase standing too close to the suit. In another episode, Launchpad starts using the expression, leading to some Secret Identity close calls. And in a later episode, the suit somehow shrinks in the wash... and its activation word becomes "blab".
 * The power suit seems to be able to hear the phrase no matter how far away the speaker is. In one episode, Fenton is hundreds of miles away and needs the Gizmoduck suit. He says the phrase and it activates, and flies across the country to get to him.
 * Not so much as it works that when Fenton is not within the suit's range, he calls it and says the word through the telephone. The reason that he had his mother use it the one time was because he forgot to turn on the suit's answering machine.
 * The actual phrase is only "blatherskite," chosen as the most obscure word in the English language. The blabbering part is just Fenton's expression, and he never realizes that he only needs to say the second half.
 * The spell that serves as a modifier for Raven's powers in Teen Titans is "Azarath Metrion Zinthos!"
 * Similarly, an issue of Teen Titans Go had the Titans' powers get juggled around, so Beast Boy ended up with Raven's magic and demonic taint. Her mantra doesn't work for him because he doesn't know what they mean, so she suggests he come up with something meaningful to him. He decides on "Tofu, Gamestation, Terra."
 * The Battletoads cartoon pilot had the three teenage protagonists shout out "Let's get warty!" to transform into their toad counterparts. A pretty stupid catchphrase, but not half as bad as what many people thought they said: "Let's get horny!" (As in horny toads. Hopefully.) "Let's get normal" was used for the reverse transformation.
 * Spoofed on The Grim Adventures of Billy and Mandy, where in one episode, Grim uses the exact same speech as He-Man to teleport his magical scythe into his hands. He has never before, and never again does need to say those words to do that.
 * Grim may have just been having fun. Despite his usually dour demeanor, episodes have repeatedly shown that under the death's hood lurks a big goofball.
 * Re Boot has "ReBoot". Simple eh?
 * Along with a tap of their symbol, usually...
 * Spoofed during Nullzilla, where the characters summon vehicles for a Combining Mecha with voice commands. Bob, Dot, and Enzo get the usual speech related to the vehicles, but Frisket barks for his and Mike has to say "Gnat, slightly annoyed, high pitched buzzing force".
 * The short-lived The Avengers: United They Stand cartoon based on the Marvel comic book of the same name had Ant-Man screaming Avengers Assemble!! followed by the transformation sequence of 3/4 of the team putting on powered armor. Scarlet Witch, Tigra and The Vision didn't wear any, being mutants and a robot respectively, so they were left out of the transformation sequence.
 * The Merchandise Driven show King Arthur and The Knights of Justice had Arthur and his Knights activate their magical armor by putting their fists on the Round Table and reciting their oath:

Knights: And we are the Knights of Justice. We pledge fairness to all, to protect the weak and vanquish the evil!"


 * This happens in "Powerstone", with the main character Falcon (and all the other ones) shouting "Power Change!" every time he tries to transform. Early on in the series this doesn't actually work, as he has no control over when he transforms. (Interestingly enough, even when he transforms by complete accident, with no control over what he is doing, he still shouts "Power Change!")
 * In Jem, a rare western Magic Idol Singer series, Jerrica would "transform" into Jem by touching her earrings and whispering, "Showtime, Synergy!" This was actually a slight subversion of the trope, however, as this wasn't a magic incantation; the earrings enabled her to communicate with the advanced computer system called Synergy, and "Showtime" was the code to tell Synergy to project the computerized hologram which changed Jerrica's appearance into that of Jem. (Synergy could be contacted in the same manner to project other holograms, usually with more explicit commands.)
 * There was also an equivalent "power down" phrase: "Show's over, Synergy."
 * The segment "Arabian Knights" from The Banana Splits had the sorcerer Bez transform into a different creature by proclaiming, "Size of a... (dog, elephant, cow, what-have-you)!"
 * Teamo Supremo's transformation sequence, which had all three of the kids jumping with Brenda's skipping rope, was always triggered by Crandall saying, "Rope me, Brenda!" (obviously not in the way shown here, though one wonders if he ever wanted it that way).
 * 90's toon, Mummies Alive had the four titular mummies proclaim "With the strength of Ra!" before going going trough their transformation sequence.
 * In Defenders of the Earth, the Phantom would activate his super-strength by chanting "By jungle law, the Ghost Who Walks calls forth the power of ten tigers." His transformation sequence would then show... varying numbers of tiger heads passing into his body.
 * In WITCH, the team transforms when leader Will holds up the Heart of Kandrakar and calls out "Guardians Unite!", then each girl calling out their element (Fire! Water! Earth! Air!). Will, being the one bestowed with "What Kind of Lame Power Is Heart Anyway" goes through three different phases throughout the two seasons: in Season One, she was first up and just GRUNTED; the first half of Season 2, the grunt was replaced with "With Heart!"; when she FINALLY gained her element in the second half of Season 2, she's shunted to the end, but says "Quintessence!". It's also revealed that this goes the same for ALL Guardians, as Nerissa and the members of C.H.Y.K.N. say this when they transform with the Seal of Nerissa.
 * "Guardians Unite" was an invention of the animated series, as the comics only had the girls naming their powers (except for Will). Also, in most other countries, the translation of the phrase is a simple straight translation. The most notable (if not only) exception is the French dub, which uses "Cristallisation" instead (even though the show was animated in France).
 * And in the comics, after "New Powers" the four girls call their element, then Will call "The power to unite them". Could be a problem if she had to do an individual transformation.
 * Princess Gwenevere and The Jewel Riders has "By the power of the (X) Stone". Which however does not apply to Kale and her Dark Stone... maybe an Evil Laugh does the job?
 * The Secret Scouts in Dinosaucers would make use of their Rings of Power by saying, "Secret Scouts ring, power up!"
 * The Iron Man cartoon of the 90's had this. When Tony needed the armor he was currently wearing to be something else, he'd call the other armor by name, and his chassis would simply change accordingly. This was a way to integrate the vast variations of Iron Man armor from the comics.
 * Captain Marvel can apparently weaponise his transformation sequence, if his appearance in Justice League is anything to go by. While battling Superman, he caught Supes in a Bear Hug, called out his transformation phrase, and the bolt of lightning that would normally have transformed him back into Billy Batson instead struck Supes for damage.