Power Copying



""Now I've got your power!""

- Mega Man, Ruby-Spears animated series (1995)

Ordinarily, someone could be severely challenged when facing off against an opponent of a different fighting style, requiring hard work and training to beat them.

On the other hand, some heroes merely have to see a special ability or attack being used a few times, and will pretty much learn it instantaneously, or be able to copy it. Most of the time, Power Copying is explicitly defined as an innate ability of the hero in question. In the name of balance, such powers may only work as long as the original power-wielder is in the hero's vicinity, or he can only keep them temporarily. If he can keep them permanently, he'll only be able to copy one or a few powers at a time, the new one overwriting the old. If no restrictions are in place, this character has a good chance of degenerating into God Mode Sue. However it goes, expect such a hero to be an Instant Expert, never having to actually train in the ability (this doesn't apply to team members with this power, who presumably have practiced using their teammates' abilities).

Contrast with Ditto Fighter, where the copying of the opponent's moveset (among other things) only lasts for a single battle/match involving that opponent.

See also Powers as Programs where powers are 'installed' and Awesomeness By Analysis where observation can grant the steps needed to initiate the power or moveset. Compare All Your Powers Combined, Adaptive Ability and The Assimilator. Supertrope of Victor Gains Loser's Powers where the character gets powers after he's defeated the enemy, and Cannibalism Superpower, where the character gets powers after he's eaten the enemy.

Anime and Manga

 * In Dragon Ball, the Kamehameha is a powerful attack that took decades for Kamesennin (a.k.a. Master Roshi) to perfect. Goku saw Kamesennin perform the attack once, and pretty much got the hang of it after only a few times. A number of other characters, including Tenshinhan and Majin Buu, use this trope inconsistently.
 * Buu seems to be pretty consistent about it actually. He doesn't always throw the attack right back at the one who used it but he copies a number of powerful moves after seeing one of the Z-Fighters use it; including 's suicide explosion attack (which Buu can just regenerate from after using) and Goku's Instant Transmission Technique (which Kid Buu uses to chase the heroes across the universe when they try to perform a strategic retreat near the end of the arc).
 * Cell had this ability as his schtick, being able to copy anything he sees just once. Thanks to his trait of assimilating DNA as well, he gains everyone's secondary powers as well, including Namekian super regeneration, Saiyan's intense resilience, and Frieza's ability to survive without an atmosphere.
 * Claude in Star Ocean EX has this ability, though notably absent in the games.
 * While on a Not a Date, Maki in Airmaster gets the idea for a new attack move simply from watching a samurai movie. She later uses it without any practice, even though the samurai is using a sword and Maki is strictly legs and punches.
 * Ranma of Ranma ½ is able to master the most esoteric combat moves within days, if not hours.
 * Ranma's ability is more about analysis and breaking down attacks to principle and vulnerability. Copycat Ken from the anime is more of an example of Mega-Manning.
 * Angelic Layer prodigy Suzuhara Misaki is able to pick up her opponents' moves on the layer after seeing them only a few times, and she picks up moves performed by real people as well.
 * Kazuo Kiriyama in Battle Royale. He can mimic the skilled martial artist Sugimura after seeing him use the moves in combat a couple of times. Even when Sugimura gains the ability to, Kiriyama quickly copies this as well.
 * In Naruto, Kakashi Hatake and the Uchiha clan have an explicit ability to copy other ninjas' moves with their Sharingan. Kakashi is known to screw with his opponents' minds by subtly hypnotising them into using techniques he already knows, making it look like he can copy their techniques before they even finish using them.
 * One of the definitive powers of Ifurita, the "Demon God" android from El-Hazard: The Magnificent World, who can copy and improve on any attack used against her. (That she's pretty much indestructible just helps her pick up things.)
 * How Urahara trained Ichigo in Bleach. Knowing he didn't have time to actually learn to fight, he just pummeled him until he learned the moves that were being used against him.
 * There's also the ninth Espada, Aaroniero Arruruerie, who has the ability to obtain the power of any Hollow he eats.
 * Several characters from The Prince of Tennis have an ability referred to as State of Self-Actualisation (Muga no Kyouchi), which allows them to subconsciously replicate any techniques ever witnessed. Some other characters, while not possessing Muga, can also duplicate their opponents' moves, giving them a mental edge.
 * While this doesn't sound like much, considering this is tennis, after all, well, it's probably better if you look into it yourself.
 * While it didn't exactly happen overnight, Kid Samurai Yahiko from Rurouni Kenshin nonetheless managed to duplicate one of Kenshin's signature techniques solely from observation—which is still fairly impressive, since Kenshin apparently went through several years of Training from Hell to master his Hiten Mitsurugi style.
 * Shishio does 'learn' moves he sees to an extent, but only to be able to perform a perfect counter rather than executing the move itself.
 * Massively subverted at the end of the manga. Aoshi fights a member of a Quirky Miniboss Squad who specializes in copying the sword techniques of his enemies. It appears to be working and the guy seems to have an edge on Aoshi until Aoshi suddenly kicks him right in the face, informs him that as a martial arts master using swords is only a part of his technique. (And the copycat can't copy his kenpo skills). The angry copycat tries to kill Aoshi with his own techniques, but Aoshi correctly anticipates the moves, comments on how dumb it is trying to kill him with moves he knows inside and out, and then promptly breaks the copycat's swords and beats the crap out of him.
 * Several of the villains in Inuyasha, most notably series Big Bad Naraku, are able to consume other demons to steal their body parts and abilities.
 * Mahou Sensei Negima gives us Ku Nel. His Pactio card
 * As of Chapters 239-241,
 * Jack Rakan demonstrates this ability too. He can use high-level Shinmeiryuu techniques from simply having seen Eishun perform them.
 * Tiger and Bunny  can imitate the power of the last NEXT she touched, a very very important plot twist.
 * In the Yu Yu Hakusho movie, Bonds of Fire, Kuwabara encounters a demon who can mimic any technique his opponent uses. After being matched move-for-move, Kuwabara tricks his enemy into copying a move that throws every single bit of spiritual energy at the target. The demon swiftly realizes he's just doomed himself, as while he can copy energy attacks, he can't copy his opponent's physical strength... and Kuwabara is far stronger than he is. Cue asskicking.
 * Gourmet, an enemy from the third season, had a Cannibalism Superpower. This unfortunately proved to be his downfall when he ate the Elder Toguro, who regenerated and took over Gourmet's body from within in the most horrible way possible.
 * According to Decepticon rumor, Thrust of Transformers Armada can copy his opponent's fighting style just by watching him. He's never actually done this in canon, but since everyone's fighting styles seem to be either "run at enemy and grab his fists forcefully", "swing sword like baseball bat" or "shoot from a distance", he doesn't seem to have a reason to.
 * In Magical Girl Lyrical Nanoha A's, the final challenge—the manifested form of the Book of Darkness—not only has her own suite of nasty-sounding attacks, she's also got the ability to copy and enhance the attacks of anyone whose magic has been used to fuel her. Which, unfortunately, includes both Nanoha and Fate. Cue our heroes bravely running like hell to escape the blast-range of Nanoha's trademark Starlight Breaker.
 * Hayate also makes use of this same power shortly thereafter to become an Instant Expert in magical combat.
 * Takeshi Yoshida, from the baseball manga Touch is able to imitate a pitcher's style perfectly just by watching them. He develops an impressive repertoire.
 * In Baki the Grappler the protagonist's Axe Crazy Blood Knight father encourages him to steal and copy his opponent's moves and techniques in part because "It really pisses them off".
 * In NEEDLESS, the protagonist and Big Bad, through the Zero Fragment, can memorize the series' huge amount of skills just by seeing it used or headbutting them.
 * In Fist of the North Star, Kenshiro reveals a martial arts ability that allows him to learn any special attack after witnessing it the first time.
 * Clare from Claymore is fairly adept at this, typically copying her allies rather than enemies.
 * Roxanne of Love and Hate did it as well, but in a much more sinister way.
 * In One Piece, Luffy is able to replicate CP9's Shave technique after watching the technique a couple of times and adapting his Rubber Man powers to allow his body to perform the task. Much later Sanji successfully discovers how to perform their Moon Walk.
 * In Hunter X Hunter the leader of the Phantom Troupe can steal the Nen abilities of others by learning about them, asking questions, and knowing its name. The original user of that ability can then no longer use that ability again.
 * In Guyver, the zoanoid Aptom has a particularly terrifying version of this power. At first he could only poorly mimic other forms: admittedly he could do this after only looking at them, but his imitations were far inferior to the originals. Once he's reworked by one of the series' Big Bads, he gains the ability to perfectly replicate any form just by getting a sample of their DNA. Except he gathers samples by melding genetic matter with his own body, and he can do this while the target is still alive. This becomes Aptom's favored method of killing, and it is lethal to amazing degrees: at one point he has contact with another character for roughly 3 seconds before being turned into shreds of skin, then atomized. In that time, his DNA-merging trick had already seeped into the other character enough to let Aptom take over with all his abilities intact, plus those of the character. Oh, and if he wants he can just let the DNA replicating system seep into someone and overwrite them without absorbing their body, meaning he can replicate himself without limit so long as there are bodies around to infect. He can even do this to corpses.
 * In Gakuen Alice, Mikan and  Yuka both have the ability to turn other peoples abilities into gems and then absorb said gems into their body, gaining those powers.
 * Nanami from Katanagatari can learn any technique she sees once, and master it if she's seen it twice.
 * In Rozen Maiden when one doll defeats another, they not only gain the defeated doll's Rosa Mystica, but can also use their powers.
 * In the manga chapters of Saki set after the Prefecture finals,, is revealed to have the power to copy any mahjong player, but she can only do it once per round per day each. She demonstrates this by using the styles of all the Kiyosumi players, culminating with her out-Rinshan Kaihoing Saki herself.
 * The protagonist of Medaka Box initially comes off as Always Someone Better, but it becomes apparent that every time she does lose to someone at something, she starts mimicking and equaling them. Post-Genre Shift, this turns out to be an actual superpower.
 * A rather strange example in Shingeki no Kyojin. Humans are decidedly weaker than the giants they fight, but much smarter. This gets turned on its head when  gains the opposite ability of Kirby; by being eaten, he can control the giant that ate him from the inside. When this first presents itself, everyone believes him to be a giant that has gone insane. Being both insanely strong and a specialist in hand-to-hand combat allows him to kill at fifteen other giants before the giant he was controlling died.
 * Actually, what happened was he generated a giant version of himself from within the giant that ate him, causing said giant to explode. He then proceeded to beat the hell out of the other giants with the giant version of himself. He is capable to generating all or part of his giant form whenever he bleeds (which is why he bites down on his thumb to transform from that point onward), though he can't really control it all that well. The reason why he first transformed after getting eaten was because the giant that ate him caused one of his arms to be severed as his arm was still outside the giant's mouth when the giant bit down.
 * Wandering Warrior Reina enters the Queens Blade competition after dueling (and losing too) several of the other Queen's Blade competitors and incorporating their moves into her repertoire, taking her from rank amateur to world champion, and later defeats her friends and allies in the competition by taking on their goals and making them her own. As a finishing move.
 * In Saint Seiya: The Lost Canvas, Leo Regulus can fully understand how a technique works, copy it and execute it better than the original user just by seeing it.
 * Mega Man Megamix: Not as prominent as other versions, but Mega Man DOES copy powers here.
 * Kise of Kuroko no Basuke has the ability to copy any basketball technique he's seen and make it his own.
 * In Kinnikuman Stecasse King, a giant cassette player, inserts tapes from the Choujin Encyclopedia into his chest, gaining the abilities of whichever wrestler the tape covers. This proves his downfall when he tries to copy Kinnikuman—the tape he has is outdated, from back in the days when the big guy was a cowardly wimp.
 * Tachimukai from Inazuma Eleven is able to copy Endou's Hisatsu Techniques just by watching him, on TV!
 * Hana from Gate 7 is described as "Not" and therefore "Everything is taken in" meaning that zhe can adopt opponents's techniques as offense or deffense as zhe likes.
 * Several enemies in the Sailor Moon anime had this ability, including the Gemini Warriors (copying Sailor Mars and Mercury), Techniclon (copying Sailor Jupiter), and Malachite (copying Sailor Jupiter, Venus, and Mars).
 * Several enemies in the Sailor Moon anime had this ability, including the Gemini Warriors (copying Sailor Mars and Mercury), Techniclon (copying Sailor Jupiter), and Malachite (copying Sailor Jupiter, Venus, and Mars).

Comic Books

 * Rogue from X-Men is possibly the best-known example in the world of comics. However, her power works on bare skin contact and works whether she wants it to or not, and sucks the life out of the victim. This has been a constant source of angst, but recently she has gained better control so that touching people isn't always a near death sentance. There have been other X-Men examples over the years:
 * Synch from Generation X, though he possibly had the second-lamest power out of the group. As he couldn't keep any borrowed powers once their owner left his radius, there wasn't much he could do by himself and couldn't even fend off a pair of human bullies.
 * Several characters said he had the potential to be extremely powerful, more than once he was shown using borrowed powers better than their original owners, and he could use his power for lots of secondary effects like identifying and tracking other mutants. It's just that none of that helps him when faced with an entirely mundane threat like a bomb.
 * Gen-X's archenemy Emplate could this too, by feeding on a mutant's marrow via the mouths in his hands. Unlike most others, however, he must do this to survive. Basically, he's a mutant vampire. His victims gain the same mouths on their hands he has, and the same compulsion to feed, also similar to certain vampire stories.
 * Mimic, on the other hand, need only be in the proximity of another mutant. He gets a bonus, too: The main Marvel Universe Mimic has permanently taken on the powers of the original five X-Men in addition to this, and his Parallel Universe double, the Exiles version, can hold any five powers at a time (though at half the original power level each).
 * Pandemic injected himself with a virus that would copy mutant powers. He is defeated when Sabretooth has him gain his Healing Factor.
 * Hope Summers, mutant messiah, has this power along with the ability to influence the mutants around her.
 * Taskmaster, of Marvel Comics, possesses photographic reflexes. He can do anything after seeing it performed once, with exactly as much skill as the person he watched had in the task. Up to and including Chow Yun-Fat. However, he gains the ability to use it, not their powers. Meaning he can do the same flips as Spider-man, but he'll never be able to leap off a sheer wall. However, he can watch a scene in fast-forward and perform it at double-speed for a (very) limited time.
 * Even more so, he uses his ability of reflecting an enemy's moves to predict what they would do next. Which got him absolutely nothing when Deadpool kicked his ass with the power of dance and randomness.
 * Echo, also of Marvel, has the same ability.
 * Cassandra Cain from DC Comics does as well as an extension of her ability to read body language. It's not so much a superpower as she's just so good at reading enemies and martial arts in general that one look is all it takes, and she can learn entire styles perfectly in minutes.
 * As does Ryan Tabbot, from Gold Digger, though his version is a bit worse in that while he can copy any move he sees, he still has to figure out how best to use it, so some highly specialized moves would get him in more trouble than they're worth if he used them.
 * The Super-Adaptoid can copy the powers of any superhuman it fights. In the Marvel Adventures series, it could also think like its target - which meant once it had copied the Avengers, it no longer wanted to fight, seeing them as the good guys now.
 * In the Guardians of the Galaxy future of the Marvel Universe, The Protege has this ability for all inherent abilities, with no restrictions and can combine them. Needless to say, she quickly becomes the most powerful being in her universe. Eventually, she tries to use these to become the new One-Above-All before getting smacked down by the Living Tribunal.
 * Over in the DCU, we have the android Amazo (created 6 years before the Super-Adaptoid), who has this ability. Just to make things tougher for the heroes, sometimes he comes with powers pre-programmed, and then copies some more. Amazo's power is taken to the ultimate level in the DCAU.
 * Also in the DCU, we have Libra. Who first appeared as a minor Justice League villain in the 70's, before Grant Morrison got hold of him and had him as one of the main villains of Final Crisis, being pretty much responsible for all the evil not committed by Darkseid personally, including for the  death of Lois Lane.
 * Also also in the DCU, the Parasitic Teutons of Assimilation, or PTA. WASPs engineered with the ability to copy any superpower they see in action. Their exact origin is a mystery, but be honest: would you really want to know?
 * Mega Man of Archie Comics. It's pretty accurate to games, though also a source of angst as Rock is inherently a pacifist who is gaining ever more powerful weapons.

Fan Works

 * Road Roller Extreme from Super Milestone Wars, a Super Robot Genre that can assume the power or Mecha Expansion Pack of any other super robot in fiction.
 * In the Alternate Universe Twilight fic Luminosity, Addy can, upon physical contact, perfectly replicate the powers of any person with special abilities (called "witches"). She can only hold one at a time, however.
 * In the Touhou fic Imperfect Metamorphosis, . By doing so, she becomes able to replicate their powers and appearances.
 * The gloriously bonkers Neon Genesis Evangelion Crack Fic A Little Angel On My Shoulder has the Instrumemory system, which is a bit different from most examples of this trope since it involves the Shoulder Angels (basically pint-sized ghosts of the canon Angels) temporarily merging with the Eva to allow it to borrow the Angel in question's abilities.

Film

 * Alice in A Nightmare on Elm Street IV: Dream Master is an interesting example. She is the one mega manning even though Freddy is the one doing the killing.
 * Po from Kung Fu Panda learns the Wuxia finger hold, and a technique to manipulate water droplets after watching them once. His master Shifu is a little bit jealous.

Literature

 * All of the competent channelers in The Wheel of Time series do this on a regular basis. Some of them even do it to each other when they intuitively leap to new things (specific example: when Egwene ties off a weave but can't figure out how she did it, then Elayne learns from her, and Egwene watches Elayne do it so that she can repeat it).
 * Protagonist Lire of Deadly Remains lives in a world where magic and Psychic Powers are real and publicly known. She normally has the power of Psychometry (read the thoughts of a person who handled an object). By touching the remains of three psychic murder victims (to read them), she gains the powers of telekinesis, pyrokinesis, and cryokinesis. With practice, she gains the ability to combine the abilities.
 * Unique among the Thirteen Orphans in Breaking the Wall, Albert Yu, representing the Cat, is able to temporarily mimic the status and abilities of any one of the other twelve traditional places on the Eastern Zodiac.

Live-Action TV
"Resistance is futile."
 * Sylar and Peter Petrelli from Heroes both are able to acquire new powers from other evolved humans. Peter just has to remember how that hero made him feel; Sylar's method is... a little messier.
 * In the graphic novels, one character, Linda, has a power that allows her to see the auras of people around her, and seemingly absorb them. Not only does it happen to absorb superhuman powers, but it allows her to kill them as well. Nifty. Unfortunately, she got a bridge dropped on her in her very first appearance, and didn't do anything too spectacular in the two other comics she appeared in (thanks to Anachronic Order). Ah, well.
 * Like Taskmaster, Monica Dawson's power is to be able to perform any physical feat she sees, from cutting a tomato into a rose like the TV chef to pulling wirework-style Kung Fu from action flicks. She receives a Blackberry with videos of various skills (plumbing, fighting, flying airplanes, etc) that she can watch to copy any time she needs to.
 * And now, the Big Bad of Season 3: Villains, is revealed to have the ability to steal powers via touch, acquiring new abilities while depowering the original owners..
 * As of Volume 4, they've significantly nerfed Peter's ability to where he can only keep one power at a time so as to cancel out his Story-Breaker Power.
 * This Left Handed Toons strip about Sylar comes ever so close to referencing the trope by name.
 * A number of examples from Charmed.
 * This was the main ability of Warlocks, the Monster of the Week enemies from the show's early seasons, which was their primary motive for hunting and killing witches. Despite their potential for leveling up, they were pretty much at the bottom of the Sorting Algorithm of Evil because they were mostly too weak to kill anything with substantial power (such as a demon).
 * Zankou, the second-most-powerful demon in existence and the Big Bad of Season 7, demonstrated the ability to absorb the powers of those he kills, but only really used this ability once.
 * Cole, after being sent to the demon afterlife, managed to avoid disintegration and found he could absorb the lingering powers left behind by all the demons sent there to be destroyed. Eventually he absorbed enough powers to kill the serpent that devoured the souls sent there and was able to return to earth, with a ridiculously large array of random abilities.
 * In Kamen Rider Decade, the eponymous hero possesses the ability to transform into one of his nine predecessors (Kuuga through Kiva), gaining all the abilities and equipment that comes with them. The only difference is that he retains his own Transformation Trinket belt, since his powers operate by using a card reader in the buckle.
 * The new Kamen Rider series, Kamen Rider OOO, uses a similar concept, with the main character having to take Core Medals from the Big Bads this series, the Greed, in order to use the powers contained in them. Most Kamen Riders have some element of Phlebotinum Rebel, but OOO is probably the only one whose powers are chunks of his villains instead of merely made by them.
 * And then Super Sentai got in on the act. In Kaizoku Sentai Gokaiger, the heroes have a stash of Ranger Keys, which unlock the powers of previous Sentai teams. Exactly like Decade and his cards.
 * And of course, when both franchises had a Big Dang Crossover, one of the main selling points was Decade and GokaiRed using their copied powers against each other.
 * Star Trek: The Borg have the ability to assimilate technology and knowledge from other species. It is at the very core of their philosophy.


 * In one episode of Stargate SG-1, the planet of the week features a civilization with nanites in their brain. They have child prodigies learn everything they can about a certain subject (one character is an 11-year-old expert on Naquadah reactors). When they reach a certain age, the nanites are harvested and distributed to the other members of the species, and suddenly everyone with a nanite has that knowledge. The downside is that removing the nanites causes their original possessor to regress to an infantile state and adding new nanites doesn't work.
 * The villain in the Haven episode "Fear and Loathing" stole powers via contact with their owners' blood. He could only keep one power at a time, so if he took a new one, his previous victim would get their powers back. But if he still has their power when he dies, the power loss is permanent.
 * The title character of the short-lived 80s show Automan could duplicate any skill he'd seen used at least once.

Tabletop Games

 * In Vampire: The Masquerade, a vampire can steal another vampire's power by devouring the vampire's soul. The game considers this act, called Diablerie, to be a Very, Very Bad Thing, especially in the eyes of the Camarilla... Though they mostly dislike it for the precedent it sets.
 * In Exalted, Eclipse Caste Solars and Moonshadow Caste Abyssals can learn the Charms of other types of Exalted, as well as Charms unique to spirits. The catch is they have to be taught the Charm by an Exalt of that type (or Spirit) who knows it.
 * In the Dungeons & Dragons book Serpent Kingdoms, the Sarrukh has an ability called "Manipulate Form" which can permanently imbue any reptilian creature with its own physical features and powers. This forms the basis of the infamous Game Breaker character "Pun-Pun", which can copy everything in the universe at the same time, with the power increased as much as he wants. By some interpretations of the rules he can even make up things to copy.
 * Oh, and this can be done at 1st level (although only in the Forgotten Realms universe). It is an important lesson in what happens when you take the rules literally.
 * There is also the Spellthief Prestige Class in edition 3.5, which has a temporary, disposable version of this trope
 * The Tyranids of Warhammer 40,000 do something similar to Power Copying. When they turn their opponents into the raw materials to make more Tyranids, they also absorb their information and occasionally their traits; these are then used by the hive fleet to make it easier to counter those tactics and abilities. Some sources also hint that some varieties of Tyranid were "invented" using the DNA of certain foes, such as the psychic Zoanthropes (believed to have come from Eldar DNA) and the durable Tyrant Guard (supposedly created with Space Marine DNA).
 * The Kroot also do something like this. They consume their slain enemies, and any useful traits are incorporated into the Kroot's DNA (which is mostly blank apart from their natural traits). Over a few generations, the traits gained from consumed enemies become a natural part of the Kroot's biology.
 * The Kroot Shapers are shamans within tribes that direct what they eat, to ensure only good traits are retained and not detrimental ones. This came after one section of kroot decided it would be good to assimilate canine DNA, and getting trapped in an evolutionary dead end. The current Kroot themselves are actually not the base race, they use to be a type of scavenging bird before consuming a humanoid race.
 * The chess variant Plunder Chess allows pieces that capture other pieces to use the captured piece's move once.
 * There's also the gruesome Pathfinder spell, Blood Transcription, which requires you to "consume" a pint of blood from a dead spellcaster, allowing you to learn one of their spells, provided your class can learn it. Needless to say, this spell comes with an 'evil' descriptor.

Toys

 * The Mask of Kindred in Bionicle. It allows the wearer to copy the abilities of ocean animals.
 * Also, the Mask of Emulation, which allows the wearer to use any power he can watch someone else using.
 * One minor character has the ability to become the master of any activity he sees being performed. This doesn't encompass powers, but it does let him, say, become proficient in the melee fighting style of his opponent. And be better at it.
 * Vezok can absorb powers used against him. He can also combine them, though it's unclear how long he can keep one power.
 * The Mega Man action figures (based on the Ruby-Spears animated series,) has this as its main feature. Every robot figure in the line can replace one hand with a spring loaded arm cannon (though only a couple actually COME with an arm cannon) and all the various weapons are completely interchangeable, which not only allows Mega Man himself to do his thing, but many other wild combinations—like having Cut Man fire plasma shots, bombs, or even Guts Man's fire hydrant from his head.

Video Games

 * Former Trope Namer Mega Man has the ability to utilize the weapons of the various Robot Masters that serve as the bosses for the series—though there is some occasional alteration for the sake of gameplay or other compatibility issues. Almost all his Expies and Alternate Universe counterparts either have this ability direct or use something based off the same concept.
 * Taken up to the extreme in Mega Man Zero 4, where you can take each and every one of the mook's weapon using your Z-Knuckle.
 * Bass.EXE has his Get ability, which he uses to absorb data to gain more power and abilities, not unlike his Classic counterpart. Which is inherited in Mega Man Star Force by the Geo Stelar/Omega Xis fusion Mega Man. If you curbstomp mooks with sufficient skill, you gain a battle card representing their attack. Usually you can use it better than they can - in 2, the Mettenna's GrndWave1, for example, does a lot more damage in Geo's hands and can hit multiple targets.
 * Some games in the Heroes of Might and Magic series feature the skill Eagle Eye, which allows the hero to learn spells by watching the enemy hero cast them in battle.
 * Considering that since you learn them from enemy heroes and are likely to conquer the towns they learned them from, skilled players more or less ignore it for better skills such as Wisdom, which is needed to learn the higher level spells to begin with. And generally the highest level spells you could get was level 4.
 * In V, this also works against spellcaster creatures, as they use the same spells. However, in neither case Eagle Eye allows heroes to learn spells that require the respective magic skill (3rd to 5th cycle) or abilities unique to the hero class (Barbarian heroes, who use War Cries instead of magic, can learn War Cries but not magic with a similar skill).
 * Metroid:
 * In Metroid Prime, Samus gets her Plasma Beam by copying what was apparently originally a beam used by the Space Pirates for mining.
 * Samus gets a missile expansion from the Dark Missile Trooper in Metroid Prime 2. The Ing item guardians are a double example; after they steal your equipment at the beginning, you can see them using it when they fight you, then you kill them to get it back.
 * In the third Prime, the Nova Beam is collected after destroying a mining platform that was using it.
 * Metroid Fusion has this trope with nearly every boss. You get the Morph Ball from the first boss that can curl up into a ball and charge at you, the Gravity Suit comes from an enemy that can manipulate gravity, the Plasma Beam is acquired after you kill a plant that shoots lasers at you...
 * In the Disgaea series, characters are able to learn magic, weapon skills, and abilities from others on their team through different methods, depending on the game.
 * In the first two games, only magic could be learned via the master and student system, which allows a character to use the spells of an adjacent unit if they were the ones who created them. The spell would be learned permanently with enough uses.
 * Disgaea 3: Absence of Justice introduces the Class World, where a character who's leading a school club can learn the magic, weapon skills, and abilities (Or "evilities", as they're called in-game) possessed by any characters in the same club, albeit for a much higher price then what they purchased them for. It also gives Yukimaru a unique primary evility that makes her to copy the primary evility of a target she kills.
 * Dark Hero Days adds the Magichange 2 ability, which allows a humanoid character to use the special attacks of the monster who performs it on them.
 * Many variations on the Blue Mage from the Final Fantasy series of games work like this. The precise variant varies from game to game—sometimes, they have to be hit by the ability, and in others they merely have to be in the party when the ability is used, and some have to do something special related to killing the enemy to do it (Final Fantasy X has you use an Absorb-like spell, while Final Fantasy IX has you eating and cooking enemies). Final Fantasy VI specifies that the Blue Mage has to see the spell being cast, so he can't learn anything if he's Blinded. In a variation on the theme, Summoners in the series often must defeat prospective summons in combat before being allowed to summon them.
 * Another variant is the Mime, who can repeat the last action taken by an ally, no matter what it was, with no MP or item cost.
 * Blue Mages in Aht Urhgan are able to use monster abilities because monster parts are grafted onto their body. Story-wise, becoming a Blue Mage is akin to selling your soul.
 * This is how Ramza learns the Ultima spell in Final Fantasy Tactics, having to get hit first..
 * Likewise, summoners learn the hidden ultimate summon in this manner. There are some other spells that can work like this (the level 4 spells, most high end summons), but those can be learned normally, which is generally less troublesome.
 * Enemy Skill materia in Final Fantasy VII also lets you learn a, well, enemy's skill that is used on you.
 * Also the Mime materia, which when equipped lets you copy what ever move was just used. This included summons and Limit Breaks.
 * Also inverted by a boss in Final Fantasy V, he can learn Blue Magic from your party. Including Self-Destruct.
 * Final Fantasy X's Blitzball mini game allows the players of your team to mark and learn new abilities from the players of the opponent team.
 * Kirby, the eponymous star of his own Nintendo video game series and the anime Kirby: Right Back at Ya!, copies the power of any enemy he can successfully eat, except for in the first game.
 * This also carried over to Super Smash Bros., although he can't really eat his enemies. He also only copies one move of the inhaled opponent, which replaces his Inhale move until you decide to drop the ability by taunting or if you take enough damage from the opponent(s).
 * In Kirby Super Star, he can even use the ability to create a "Helper", an ally with similar abilities to the enemy that commonly has the skill (often a Palette Swap). The helpers themselves has a bit of Mega Manning; if one's health is reduced to zero, they begin to glow before exploding. In this state, they simply need to touch an enemy to turn into that enemy's respective helper and completely restore their health to boot. One of the abilities also allows Kirby to copy powers by scanning the enemy rather than inhaling them. This is rather pointless for Kirby, but gives the Helper even more freedom.
 * Said ability can actually be used on Scarfies to get Crash (as they can't be enhaled).
 * Played with in Milky Way Wishes, where Kirby cannot copy enemies by eating them. Kirby has to find them in capsules hidden throughout the levels, which lets Kirby can select that ability at any time from the pause screen, much like Mega Man.
 * Shanoa in Castlevania: Order of Ecclesia is able to perform power-copying feats by absorbing magical glyphs. In several cases, she can steal a monster's magic in the middle of battle.
 * Don't forget Dimitrii from Dawn of Sorrow, who can copy Soma's magic souls by being hurt by them... However, it makes him a pathetically easy boss if you know what soul to use on him - he will copy that attack, no matter what it is, so making him use a weak and easily avoidable attack makes the battle a cakewalk.
 * In X-Men vs. Street Fighter, Rogue's power-stealing abilities are represented as a special move that allows her to copy one of her opponents' special moves by kissing them. In Marvel vs. Capcom 2, this power couldn't work because there were 56 characters total, so instead it gives Rogue a bonus to various stats like Attack, Defense, Speed, or Health.
 * She can also steal the Shun Goku Satsu and use it.
 * Musashi: Samurai Legend allowed you to copy the moves of any enemy by completing a button-press sequence.
 * The game to which Samurai Legend is a Spiritual Sequel, Brave Fencer Musashi, also allowed Musashi to copy enemy moves by absorbing the enemies into his shortsword, the aptly-named Fusion. He could only hold one at once, though, as opposed to Samurai Legend's version being able to learn as many as he pleases.
 * The Pokémon series has a number of examples:
 * Mirror Move and Copycat mimic the last move used by an opponent, while Me First can mimic an opponent's move before they use it.
 * Mimic teaches the user one of the opponent's moves for the duration of the current battle, allowing them to use it up to five times.
 * Sketch teaches the user one of the opponent's moves permanently, and is exclusive to the Pokemon Smeargle, who learns a new Sketch every ten levels. With enough time and effort, a player can potentially teach Smeargle any move in the game, although Smeargle is by no means a strong fighter. A male Smeargle can thus be used to breed any desirable move onto any baby Pokemon in a compatible breeding group.
 * In Sonic Adventure 2, Sonic is able to use Shadow's ability of Chaos Control after seeing him use it just once. Though it's implied that he always has had that power. That moment was the time he found out about it.
 * Sonic Chronicles gives us the Gizoids, of which Emerl was the most powerful. Though unlike Emerl, who doesn't seem to have a limit in what he can copy, the Gizoid Mooks are only capable of copying one or two special attacks from the main characters.
 * The final boss of Sonic Heroes copies Chaos Control from Shadow, Chaos' ability to manipulate water (Though in this case, he uses metal) from Froggy and Cheese and everyone elses' own powers.
 * To a lesser extent, the Chao. They can absorb the power and some physical traits of any tiny animal presented to them. They can mimic the physical traits of their owners, to some extent- the Sonic and Shadow chao being the prime offenders.
 * Jade Empire seems to teach new fighting styles to the player character this way.
 * Knights of the Old Republic II, does essentially the same thing. On the dark side path, the player character can learn complex lightsaber techniques and Force forms from Jedi Masters while fighting them. To be fair, the Jedi Masters do protest that this is impossible...
 * Revolver Ocelot from the Metal Gear Solid series falls squarely into this trope. According to the supplemental material, after merely witnessing a tactic on the battlefield, he can them use said tactic thereafter. This certainly explains his ludicrous skills with revolvers, but he is noticably clumsier as his younger self in Metal Gear Solid 3: Snake Eater, where Snake calls him out on using a tactic he's only just seen in battle.
 * At the end of the game
 * In the Legacy of Kain series, Raziel and Kain steal their enemies' abilities by devouring their souls/blood in Soul Reaver and Blood Omen 2, respectively. One review of Soul Reaver actually referred to Raziel as "a sort of demonic Mega Man" for this reason. Interestingly, Raziel actually keeps almost all of the abilities he gains this way in his first appearance through his next two.
 * Shirou of Fate Stay Night is a rather Inept Mage in most aspects, but he eventually discovers that . In the final route of the game,  seems to exhibit a form of this, as well, gaining form and intelligence by eating the hearts/bodies of his opponents.
 * In the obscure Cyberpunk FPS game Cyber Mage by Origin, one of the ways the titular character can gain new Darklight spells is by allowing them to hit him, so that the crystal implanted in his forehead can replicate the spell. You can do this either by letting enemies cast the spell on you, or by finding Icons that cast the spell and shooting one into a nearby wall.
 * The only way to learn new attacks in Digimon World for the PSX is to get hit by an attack your current Digimon can use.
 * Additionally, you can also train their Brain stat with the Classroom, but that takes much longer and is less likely to happen.
 * One of the characters in Live a Live is a professional fighter who is determined to become the best in the world. He learns new techniques from his enemies by having them done to him.
 * The King of Fighters's Rugal Bernstein was apparently originally supposed to be able to do this, taking your attacks and turning them back upon you, but due to memory constraints, he was given Geese's Reppuu Ken and Krauser's Kaiser Wave, with the explanation that he had fought those men before. He also has his own version of Athena's Psycho Reflector, called Dark Barrier.
 * Kingdom Hearts II has that and the Drive Forms. Each form's fighting style is a reflection of the person from whom the form is derived:
 * Valor Form: Reflects Goofy's all-physical, up-close-and-personal fighting style
 * Wisdom Form: Reflects Donald's all-magic, distance-oriented fighting style
 * Master Form: Reflects Mickey's fighting style, using physical, magical, up-close, and distance attacks
 * Final Form: Reflects fighting style, using lightning-fast attacks and both Keyblade and  attacks
 * The Final Mix-exclusive Limit Form reflects how Sora fought in the first game, using some of the special moves that were usable in Kingdom Hearts 1, but not the original sequel.
 * Clive Barker's Jericho sees use this when you fight it.  Makes for some awesome animations; most notably the aerial duel between  and the beatdown handed to it by Church.
 * Devil May Cry 2 employs a variation of this. The penultimate boss, Argosax the Chaos, is a twisted amalgamation of bosses from all through the game and its prequel; those bosses being Phantom, Griffon, Furiataurus, Nefasturris, Jokatgulm and Oranguerra. Each has its own health bar and the player must kill them all, one at a time, before going on to face the Despair Embodied.
 * SaGa Frontier has a single instance of this in Alkaiser's story. In the fight against the Affably Evil robot version of himself, upon using the move Dark Phoenix, Alkaiser can use his own special move in response to seeing his in order to learn his ultimate ability, Re-Al-Phoenix.
 * Also Monsters, and Riki in particular, are based entirely around absorbing enemies and mix-and-matching their moves.
 * Mystics can seal monsters into their "mystic" weapons to learn moves as well gain a stat bonus.
 * The Breath of Fire series. In many of the titles, you can copy specific enemy abilities by simply witnessing them (in III it was a Examine command, and in IV you merely had to be Defending.).
 * If Anastasia Romanov (yes, that Anastasia Romanov) of Shadow Hearts: Covenant takes a photo of certain enemies, she can "cast" a spell of theirs by "summoning" them with a photo.
 * Marisa Kirisame of Touhou has a variation on this, where she actually steals the spells or spellbooks of others. She has only a small few spells that are actually of her own design (and rarely even uses them), even her own signature move was stolen from Yuuka (although since Master Spark seems to be an innate ability, it seems to be a more 'pure' example of this trope than spellbook-based Non-Directional Laser.) Since spellbooks are specifically stated in canon to be illegible to anyone who is not at least as great a mage as the one who wrote the spellbook when they wrote it, the fact that "mere" human Marisa can swipe powers from Patchouli, much less Yuuka, however, implies she has at least in some way earned her powers.
 * It is worth noting that Marisa's versions of the spells she copies are often weaker than the originals in some way. Her Master Spark is smaller than Yuuka's, her Non-Directional Laser requires more power to cast, and her Orreries Sun cannot be thrown. She makes up for this by developing new spells which use the copied one as a base, often turning them Up to Eleven (Final Spark/Final Master Spark/Blazing Star, Starlight Typhoon and Orreries Solar System respectively).
 * Humorously, in the Windows era Marisa is something of a Composite Character of her prior incarnation and various other PC-98 characters. She has copied her appearance and personality.
 * One of the official supplementals, "Grimoire of Marisa", uses this as its framing device. Marisa compiles a list of other people's spell cards, and ranks them according to how useful it would be to copy them (rejecting many based on her inability to copy the Required Secondary Powers, her doubts on her ability to control them, or... well... because they're not worth the trouble to steal).
 * Also from Touhou, Satori Komeiji of Subterranean Animism is able to copy your partner's spellcards with her mind-reading powers, making her stage a Nostalgia Level.
 * Shin Megami Tensei: Devil Survivor has a system in which your characters can "crack" the skills of demons or other demon tamers, gaining the skill to equip for later or immediate use.
 * The Maw features the titular character as an Extreme Omnivore. When it eats certain unique enemies, it can also gain their powers, such as fire, flight, or shooting laser beams from its multiple eyes.
 * Marivel of Wild ARMs 2 and Emma of the Wild ARMs 1 remake build up their skill set by stealing/downloading the abilities of the monsters they meet.
 * As a Mega Man homage, Rosenkreuzstilette has Spiritia plays it straight, Grolla averts it, and Freudia uses an odd variation by retooling the attacks to fit her Ice Person status.
 * One of the most popular skill builds of Ragnarok Online's rogues (and stalkers) involves using their Intimidate ability to copy the most recent skill they've been hit with, from player or monster alike. Only stalkers have an ability to preserve the copied skill, however.
 * Guild Wars has the mesmer profession which has access to a selection of "steal" skills, which enable them to use a random skill from the enemy's bar for 20 seconds.
 * Not entirely random : depending on the skill that is used, a certain type of skill (spell or non-spell, for instance) can be copied. There's also a skill that allows to copy an ally's Elite skill, potentially allowing the Mesmer to have two Elite skills at once for a limited duration. And the Echo skills that copy one of the Mesmer's own spells.
 * Defeating anyone in Blood Storm would give the player a designated move.
 * Spellsteal in World of Warcraft pretty much works like this, although only for abilities that create a magic effect aka buff on the caster, which the spell transfers to the mage as the name implies.
 * A more straight example with the Death Knight "Dark Simulacrum" ability, which, when cast on a target, allows the death knight to instantly cast the next of the target's spells that uses mana without losing any effectiveness (For one cast, at least).
 * In Warcraft 3, the same spell could also be used to steal summoned creatures from the enemy.
 * The sneak preview at the upcoming expansion's talents gives us the Druid's Symbiosis ability which will copy one spell from the targeted player. That player will receive a druid spell.
 * Command & Conquer: Command & Conquer: Red Alert 3 features the Hammer Tank, which steals the weapons from the vehicles it destroys.
 * Each time you defeat one of the five evil pigs in Tomba 2, you get a special robe that will let you use the elemental magic of the evil pig that you beat.
 * A darker version in Myth. As part of the Vicious Cycle, the Leveler, a dark god that destroys the world every thousand years, reincarnates the last hero who defeated him and turns them into the next Leveler.
 * Viewtiful Joe has Joker, a recurring King Mook Mini Boss. In your first encounter with him, his combat skills are limited to the standard Bianky punches and kicks, but in subsequent encounters, he adds additional abilities used by other Mooks to his repertoire until your last encounter with him where he has learned most of them.
 * In the Roguelike Brogue, your Monster Allies can study (or consume) the corpses of monsters to gain their abilities: things like teleportation, being immune to fire, or flying. Yes, you can have permanently flying Tentacle Horrors following you around.
 * In The Elder Scrolls V: Skyrim, the player, as the Dragonborn, has the power to absorb the souls of slain dragons, which can be used to unlock shouts, the incantations that give dragons their powers.
 * Bravely Default, which is a Spiritual Successor to Final Fantasy, has the Vampire class, who learns certain spells by being hit just like in most Final Fantasy games.
 * Battle Golfer Yui: Yui Mizuhara learns the skills of her opponents through various means.

Web Animation

 * The magical Crystal of Absorb from Unforgotten Realms gives one the power to take on the powers of a dead opponent. Rob instantly equates this to being "like Mega Man".

Web Comics
"Black Mage: When Sarda casts a spell to hurt you and you learn that spell, you learn to cast a spell that hurts you."
 * Red Mage of Eight Bit Theater can copy the last action he's seen, though only once. This is because his class was changed to Mime—a real class from the Final Fantasy series—but the author uses it for occasional references to Marvel's Taskmaster as well.
 * Also on 8-Bit Theater, Black Mage has the blue magic ability to learn attacks from others. Naturally, since he's the official Butt Monkey, he has the most inconvenient form of blue magic - he needs to get hit with an attack to learn it. One of the only three that he's learned actually keeps him as the target when he uses it.


 * Chocolate Milkmaid can absorb the powers of anyone she "takes in a part of". Bodily fluids count. All of them. But it only works when she's in Milkmaid mode.
 * Max from Asperchu can copy an enemy's abilities by swallowing them, due to being an Expy of Kirby.
 * The Big Bad of Akuma TH is The Undertaker, a demon with the ability to copy and absorb a person's soul, gaining that person's strength, techniques, and knowldge.  Gemel from Tony TH learns any move that he personally sees. When the two meet during a crossover, The Undertaker briefly discusses the different methods that can be used to perform this trope.
 * Bob and George only lets Mega Man copy powers during the parodies of the games themselves. Given the nature of the series, what he can actually do with the powers is often extreme.

Web Original

 * Chaka, at the Super-Hero School Whateley Academy in the Whateley Universe, has the ability to manipulate Ki and see it flow. When attacked by a ninja using a secret "paralyzing nerve strike", she watches him as he tries it on her. She blocks it, so he never finished the move. She promptly uses it on him before he can react, having learned it in less time than it takes to execute the complete move once.
 * The second time she meets that ninja, she witnesses him finish off another student beforehand with a Kamehame Hadoken. When she fights him shortly after, she takes him out in a Quick Draw battle, using the blast back against him. She names it the "Chaka Chaka Bang Bang". Chaka stealing Daikon's moves seems like it's one instance away from being a Running Gag.
 * Also, 'mimic' abilities are one possible subcategory of mutant powers in that setting, though the copy isn't usually quite as good as the original. For example, Sahar has the ability to 'collect' other people's specific psychic knacks, and Counterpoint is a school bully who deliberately tries to goad other students into fighting him so he can copy their powers and beat them up even worse next time.
 * Jasmine, from Trinton Chronicles, has the ability to copy all the other superpowers she is with-in range of. This being said her power is kind of useless against others with the same or similar ability. Jasmine has copied so many powers at once she seems to have no limit, she also tends to use them like 'toys' in some cases including copying the power of a transmuter to transform junk into gemstones and the power of mentally interfacing with technologies in order to turn on her apartment's electronics and dial the phone without ever touching it.
 * Taltos does this also only using his own power of Nemesis against several of the heroes in Hallow's Eve
 * In the crossover of Smash Bros Lawl, The Irate Gamer has this as a signature move, but with the twist that the powers he copies are very underpowered versions of the originals.

Western Animation

 * Ben 10 later gained the ability to turn into any alien the Omnitrix got a DNA sample from in the third season, allowing him to transform himself into slightly-altered versions of a small handful of that season's Aliens and Monsters. To date, each of these three forms has been used exactly once, and the plot point seems to have been dropped, although it was picked up again in Ultimate Alien.
 * Ben's nemesis Kevin 11 started out with a similar ability, which he used to copy Ben's powers. After getting Ben's powers, his original ability was never seen again (except in an "alternate future" episode where he had used his ability absorption to steal traits of thousands of aliens, basically becoming a cross between Naraku and Sylar).
 * More recent seasons have Kevin as a sidekick, having found a way to return to human form. His power is the absorption ability he originally possessed, although he only uses it to absorb matter instead of copying powers. It's explained in a much later season that his power copying is a Dangerous Forbidden Technique that turns members of his species evil and insane.
 * The Big Bad of MIB: The Series was Alpha, the human founder of MIB, who merged with an alien artifact that allowed him to absorb the body-parts of aliens into his own, allowing him to cheat death and also resulting in him turning into a rather grotesque patchwork lifeform (with the abilities and attributes of all his alien body parts).
 * Blackarachnia from Transformers Animated can drain powers with a touch, similar to Rogue (except she can turn it off). Lockdown, similar to Alpha, steals body parts from other Transformers, and is essentially a Frankenstein's monster-like assembly of parts.
 * The already unstoppable, unyielding Beast Planet in Shadow Raiders is implied to be able to do this when it
 * Twilight Sparkle of My Little Pony Friendship Is Magic is capable of this. While most unicorns are capable of a little magic that helps them in their special talent, Twilight's talent IS magic so this allows her to easily copy spells used by other unicorns.
 * The Shushu Anathar from Wakfu can copy the magic of anyone he touches. He can even those use their magic better than they can. When he copied Yugo's power he could create dozens of portals at once while Yugo is only able to create one pair of portals at a time.
 * Mega Man again. In the cartoon he could seemingly only keep the power for a few minutes/shots, but he stole a Robot Master's power at least Once an Episode, usually with stock footage.
 * As evidenced by Mega Man's most (in)famous utterage of the page quote, this didn't alway work out for him.

Real Life

 * The nudibranch, a type of mollusk sometimes called the "sea slug," feeds on jellyfish and other stinging sea creatures. It is capable of taking the "stinging" cells from the creatures it eats and incorporating them into its own body, sometimes becoming more deadly than the animals it preys on.
 * Photuris fireflies first learn and mimic the blinking pattern of a different genus' females, then devour the attracted males. They can then absorb the devoured male's defensive toxins and use them for themselves.
 * It was believed by some cannibalistic tribes that eating a dead person's brain allowed you to learn their life's experiences. This unfortunately meant you could also gain the exact same disease they probably died from.
 * The most common version of this was when warriors would eat the brains or hearts of vanquished enemies to gain their strength or energy.
 * The Belgian beer industry is home to several strange and exotic beers but is fully capable of mass-producing less bizarre styles that originated abroad, like porters, stouts, etc.
 * The concept of sympathetic magic can work like this: the Bimana of Africa decorate their hunting shirts with mouse skins for speed, animal claws and teeth for ferocity, and so on.
 * Rabies. A deadly example but the trope still works. Rabies does not just spread via bites but also from eating something with rabies. Without treatment, this can be fatal but before death hits, "Rabid" strength, speed, ferocity and foaming at the mouth can be enjoyed.
 * Bruce Lee's Jeet Kune Do works on the idea of "absorbing what is useful". Lee's personal style combined his best moves from Wing Chun, Tae Kwon Do, western boxing, fencing, and escrima. Anyone adhering to this concept of martial philosophy can build their own style by learning from different ones.