The Joker is more known for being murderous and unpredictable than being an amazing hand-to-hand fighter, with only a handful of adaptations showing him as any physical match for Batman. Here he was given enhanced strength, agility, and dexterity. In the first episode he was climbing all over the place like a monkey, though this was toned down in subsequent appearances.
The Penguin is likewise an exceptional combatant, a far cry from his usual portly, nonathletic portrayal. (This is more a case of Older Than They Think, as Depending on the Writer the Penguin has been written as a skilled judoko and a physical match to Batman, while other writers elect to use the above interpretation, often for easier story telling.)
In The Batman, the Terrible Trio were social outcasts at Gotham University who stole the Man-Bat formula and became werebeasts for Batman and Batgirl to fight.
Justice League Unlimited gave this to Aquaman compared to Superfriends (the comics version was always pretty badass). They ended using almost any "joke" character in the past to great effect.
Aquaman is fifty times more OUTRAGEOUS than his typical portrayal.
The Question is shown beating up on parademons. Double-sized parademons. These are Mooks that can give Superman at least a little trouble (and think of how strong something has to be compared to a normal human in order to give Superman trouble).
In the Terrible Trio are Arrogant Kung Fu Guys who betrayed and killed their master, controlled a clan of Shadow Ninja and planed to take over the city. Oh, and they also stole a talisman that turned them into werebeasts too.
In the comics Clock King was a gimmicky joke villain whose powers were usually treated as fairly useless (think Superfriends Aquaman). TAS showed just how useful and creative his talents could be.
While the Rupert Thorne of the comics has mob ties, in TAS, he's takes over Carmine Falcone's role as Gotham's most powerful crime boss. He also takes over Sal Maroni's role in Harvey Dent's fall from grace and transformation into Two-Face.
The Riddler was changed from a character that declined into being a pathetic has-been in the contemporary comics into a smooth intellectual who presents riddles and puzzles so believably challenging that in his premiere episode, he is able to largely achieve his objective and escape Batman. As with many elements of B:TAS this filtered back into the comic books, but the extreme difficulty of writing a competent Ridder has still limited his use.
This series took Alfred Pennyworth up a notch, playing up his experience at MI6 from the comics and actively helping train Bruce Wayne and Batman for combat (his first scene in the pilot has him staging a mock attack on Bruce to gauge his readiness, and calculates the number of strikes it took and should have took to subdue him). He also helps Simon Stagg and Michael Holt escape from Professor Pyg and Mr. Toad; and manages to pull a shotgun on Silver Monkey when he invades Wayne Manor.
On the villain side of things, Cypher goes from being a plains-clothed hypnotist to a stealthy cyborg with a rather creepy method of mind-control.
Electro could get pretty lame in the comics, with his power just about enough to almost kill the web-slinger once before getting beat every time after. In this version however, he was a Big Bad by the last episode of the story arc in his first appearance, replacing the Red Skull as the primary threat. The guy then easily dispatched the Six American Heroes (a team of Golden Age heroes which included Captain America), the Insidious Six, and Spider-Man, and made it clear he could kill any of them at any time, took control of the Earth's satellites through the electrical signals he fired to broadcast himself to the world's media, announce he's the new President Evil of the world, and when all of S.H.I.E.L.D. chose to disagree, he handled them single-handedly by shooting down their base:
(Nick Fury jumps off the collapsing S.H.I.E.L.D. base, then pulls his parachute)
Female S.H.I.E.L.D. Agent:(on Nick Fury's earphone) Agent Nick Fury, do you copy?
Nick Fury: I copy, what it's worth. He took down all of S.H.I.E.L.D. with only a gesture. Heaven help us all.
(S.H.I.E.L.D. base crashes in the sea then explodes)
The series turned the Spot into a genuine threat, capable of running rings around Spider-Man with his ability to create masses of portals. Since the Spot always had dangerous powers in the comics, this was accomplished by making him not a moron.
Comics-verse Black Cat is a Badass Normal who occasionally wields bad-luck powers. Here, she starts out as a classmate of Peter's before gaining powers from the Super Serum that created Captain America.
Jason Macendale's Hobgoblin, in the comics a sad wannabe who always lived in the shadow of original Hobgoblin Roderick Kingsley, is a much more respected and feared foe here, since Kingsley is absent from this continuity.
Electro is a Badass here too. Starting out like his B-list comic self, he gets upgraded into being more like the Ultimate and 90s cartoon versions, with unlimited control over all things electrical within his range, and his range seemed to be "everywhere". If he'd been capable of saying "screw fighting you guys, I'm gonna Take Over the World; good luck punching living electricity!" he could have done so. His real weakness, established throughout the episode, is that for all his newfound power he still thinks like a B-list hood.
The Sandman took the ability to add the sand around him to himself to its logical conclusion. You know why that island you're on isn't on any map but SHIELD's, with a "seriously don't go there, for reals" warning? Every single bit of soil on the island is him, making it a Genius Loci that doesn't like you. Taking the smallest bit of him - oh, like the dirt on your clothes after you think you're done fighting him - back to the mainland would be bad. Using no powers he doesn't have in other continuities, just being smarter about how he used them and having a reason to be really pissed, it was very nearly "arrivederci, North America."
Here, Aqualad is a water-bending Atlantean cop who was lusted after by Raven and Starfire (for one episode, at least). Not too bad considering he was written out of the original Teen Titans comic book because the writer thought he was useless.
Raven as well. In the comics, she can simply teleport, heal other people, and sense other's feelings (nothing actually useful during a fight). Here, she uses telekinesis, can fly, knows sorcery, etc.
Killer Moth. In the comics, he's the most ineffectual of the Ineffectual Sympathetic Villains with a completely ridiculous costume that looks like it was put together by a colorblind tailor. Here, he's a half-man, half-moth hybrid with an army of genetically modified bugs at his command.
Kid Flash also counts. In most incarnations, the writers have to work around his Story-Breaker Power of Super Speed. Here, they take it and use it to his full extent, and he spends most of the episode running circles around the Hive Five. The only way they manage to bring him down is by tiring him out, and that takes a long time.
Madame Rouge. In the comics, after a short tenure as a recurring villain, she winds up Killed Off for Real and a source of guilt for Beast Boy. Here, her powers (stretching, Human Shifting) are greatly upgraded, making her an unholy fusion of Reed Richards and the T-1000. Nothing hurts her, except heat, and she just has to take a second to shapeshift into an undamaged form. The episode with Hot Spot alone being hunted by her makes her almost Nightmare Fuel, an implacable threat that can come from anywhere, look like anyone, and can't be held back for long even when your power is her Kryptonite Factor, and when she returns to battle Kid Flash, she's every bit as Badass. He runs circles around the HIVE Five and looks so good doing it... then she shows up and it's a whole 'nother story, able to shift fast enough to actually stretch out to grab Kid Flash when he's looking like a yellowy blur and then proceed to lay down a beatdown.
In Celebrity Deathmatch it would likely be easier to list the celebrities who did not qualify for this Trope. Even the ones who were pretty badass already (such as WWE stars) were even more so here.
In Sonic Boom, there's Shadow. He's already a strong character in the original games, being about evenly matched with Sonic, Tails, or Knuckles. In Sonic Boom, however... He chains Chaos Spears and Chaos Blasts together, not even bothering to wait more than a few seconds between attacks, is still just as fast, uses Teleport Spam even more than his original self (without any Chaos Emeralds), and does a variant of the move he does in Sonic the Hedgehog (2006) to take out an army of Mephiles clones - Only this time, he doesn't even need to remove his Inhibitor rings. He's easily able to fight Sonic and Tails at the same time.
Bumblebee, once again, featuring in Transformers Prime. His first foray into robot combat in the pilot episode had him coming to Arcee's aid by driving off an overpass, transforming, landing with a thud and by the next beat his fist connects with an Vehicon's face. He doesn't appear to be quite the same bruiser as in the movies, but he is no less reliable.
Starscream was a Running Gag of one transparent backstabbing plan after another, often openly telling Megs what an idiot he is and how Starscream should be in charge, and only being kept alive because his Megatron was no brighter than he. Certainlaterincarnationshowever are nigh unto Magnificent Bastard class, and the second-most-powerful Decepticon next to Megs himself to boot. At one point in Transformers Cybertron, he borrows a portion of the power of the god Primus and spends an arc handily kicking around all the Autobots and Decepticons singlehandedly.
Megatron himself. G1 Megatron was Too Dumb to Live when it came to Starscream, and would trust him again ten seconds after being shot at by him. "Decepticons, retreat! RETREEEEEAT!!" was practically his Catch Phrase, and the series' most diehard fans admit that he'd yell it when the going got tough even if he still actually had the upper hand. Oh, and he turned into a gun that couldn't move or fire himself and was usually held by... go on, guess who. Since then, he's had highly Badass vehicle and beast modes, and has been freakishly powerful and/or a brilliant Diabolical Mastermind.
The first real sign of this was actually in the original movie, where the two of them slaughter a good dozen named characters in the first hour. This scene, intended to get rid of old product, showed just what they could do when freed of the constraints of Contractual Immortality, and though it didn't carry into the rest of the series, later incarnations have proudly carried the flag.
Both Starscream and Megatron have outdone themselves here. The latter's a soulless Bad Boss who coldly tortures his enemies and allies, and plots to use his Necromancer abilities to raise the dead of all Cybertron as an army. Starscream, not to be outdone, has become a sociopathic Bastard Understudy who casually murders a named character in the first ten minutes of the show, and successfully betrays Megatron some episodes into the series. Unfortunately for him, it doesn't last.
Arcee, who in her G1 cartoon incarnation is presented as just The Chick, here is presented as a badass Action Girl.
Wheeljack in the original cartoon he is presented as something of a Mad Scientist archetype, edging into Gadgeteer Genius due to his tendency to invent things (and build the Dinobots). This carried over to similarly named, similarly-designed characters in both the movies and Animated series. Prime, however, turns him into a Dual WieldingSamurai Cowboy with a love for mayhem and explosives, an ace pilot, and a former Wrecker to boot.
The G1 version of Soundwave didn't do much to stick out from the rank and file other than have a cool voice and shoot a bunch of minions out of his chest. The Prime version, on the other hand, looks like a mechanical Slender Man, is eerily silent and frighteningly efficient, and happens to be one of the few Decepticons that can give the aforementioned Wheeljack a run for his money.
This series's version of Megatron is this writ large - he went from being able to just barely match Optimus in combat to being able to outclass a team of Autobots plus Optimus put together (with an arm missing). He's also much less willing to retreat, and usually wins (or at least concludes the episode on favorable terms) whenever he heads out personally. If that wasn't enough, he's also quite intelligent.
Wasp gets to take a level in badass for this cartoon. In the comic, Janet "Wasp" Van Dyne has the power to become small and shoot mildly painful "stinger" energy blasts. It's... as useful in combat as it sounds. In the series, she'll fly circles around enemies, is as capable of dealing with villains on her own as any of her teammates with her much-stronger stingers, and makes Spider-Man level wisecracks all the way.
On the villains' side, the Grim Reaper is definitely far more badass and sinister than his comics version. In the comics, he wasn't a good fighter, was pointlessly racist and non-functionally crazy, wore purple spandex with goofy, Galactus-style head gear, and was a joke in that regard. In the series, he wears a dark hoodedcape and is a Soft-Spoken SadistPsycho for Hire with a Slasher Smile. He effortlessly broke into and out of a prison that was designed by Tony Stark and guarded by SHIELD, and can slash Hawkeye's arrows and Cap's shield from mid-air with his scythe.
Believe it or not, Hulk has this in a way. He's not just the team berserker that they point at something to hit. This Hulk is smarter (think how he was in World War Hulk, for example) unless he's pissed off beyond belief (at which point the villain simply can't win anyway). Notably, there's almost no Hulk Speak to be found, he understands and uses sarcasm, and got Hawkeye to stay with the team by teasing him. And his favorite teammate is Wasp. So if you do hurt her Adaptational Badass self, you get to deal with him.
In The Adventures of Super Mario Bros. 3, she single-handedly foils Koopa's plan to have his kids take over the continents. After escaping from captitivy, she blows up the obstruction in the Warp Pipe to the Real World. Even the Mario Bros. and Toad were impressed.
In X-Men, Jubilee's fireworks are quite powerful, to the point of being as good as Cyclops' power beam. In the comics at the time, her powers were mostly a distracting light show that she'd flash into opponents' eyes (with the very recent retcon that if she was really mad, they could go kaboom. The show runners took that and ran with it). When she pulls her Cool Shades down over her eyes, that's your cue to run fast and run far!
Klarion the Witch Boy is a full blown Lord of Chaos and arch rival of Doctor Fate in this series instead of being just another magic user. He's still as childish as ever, though.
Mister Twister, originally a rather feeble villain whose powers came from a magic stick, becomes an incredibly powerful android who effortlessly solos the team (up to and including Superboy) while spouting arrogant one-liners left and right.
Count Vertigo, instead of being a guy who makes people dizzy, is a power-hungry despot trying to kill the queen of his country who's more of The Chessmaster than anything else. His superpowers are more an afterthought.
The Big Bad of season 2, the Reach are vastly more powerful than their comics counterparts. In the comics they are a weak military force using subterfuge and trickery to take Earth in a century, with an enforcer who could be beaten by a single hero. Here they are a full fleet of warships, and the Black Beetle took out Mongol in single combat. And according to Impulse's future, it only takes them a couple decades to conquer Earth.
A bit more subtle than most examples but Angmo-Asan, The Red King in The Super Hero Squad Show can backflip more than 20 feet and send the Hulk flying with a single well-placed punch; feats that he needed to use Powered Armor to do in the comics. He could probably defeat Captain America or Iron Man with just his bare hands in this incarnation. He still can't quite go toe to toe with the Hulk on his own... but it's a start. He also becomes a very amusingLarge Ham.
The Tasmanian Devil on Looney Tunes is described as a "vicious, evil-tempered brute with jaws like a steel trap, and he certainly lives up to his reputation. Compare that to a real Tasmanian devil, which may be more badass than most marsupials, but not as much as the one in the cartoons.
Matt Olsen, prior to the comics turning him in to a failed version of The Obi-Wan. In the cartoons, Matt was a normal guitarist who, after getting fed up with Will ditching him on dates, decided to find out what the hell was going on. After finding out her double life, he decided he wasn't going to stand there and let her get hurt all the time. Not only does he take combat lessons from Caleb, he also gains a massive power boost when he's forced to take up a fraction of the Heart of Earth, putting him at equal (if not greater) footing of Will herself!
Caleb himself is a Badass rebel leader in the series who is much more of a fighter than the original and doesn't spend most of the series as a flower because of Phobos, either. A fan only familiar with the comics who read this page would likely say "back up a sec, Caleb is giving somebody combat lessons?"
His underlings the Mutants (now members of the other animal races populating Third Earth) continue the pattern, with the Jackalman and Monkian analogs Kaynar and Addicus in particular portrayed as vicious, ruthless criminals before being appointed generals in Mumm-Ra's forces, and devastating fighters in battle.
The toy line has always been rather peaceful. However being an 80s cartoon, the original cartoon was considerably darker and more action packed so several characters became more Badass than before.
Megan is a normal little girl in a pretty dress in the toys. She plays the role of insert character for kids and is also just one of the kids the ponies are friends with. In Rescue from Midnight Castle she's a farm girl tomboy and a badass. Future incarnations give her a Girliness Upgrade but she's still quite capable, smart, and the Team Mom.
In My Little Pony: Friendship Is Magic, this happens to pretty much everypony sharing their name with a previous-gen pony. Rainbow Dash and Applejack are near-unrecognizable compared to G3 Rainbow Dash and G1 Applejack - the former goes from basically having FIM Rarity's exact personality, dahling, to being much more athletic and competitive, and does things like demolishing an old barn by flying into it at Super Speed causing a rainbow-colored mushroom cloud, while the latter goes from having a whole song about how she's a silly pony, to pretty much becoming The Big Guy of the series, being a tomboyish cowgirl. Sweet Apple Acres' apple harvesting method is basically "Applejack kicks the tree so hard that all the apples fall at once while everyone else runs around with buckets." Pinkie Pie goes from being vaguely similar to her G4 self, but very bland (like most G3 characters) to being Crazy Awesome. Rarity goes from a naive child to a competent and experienced fashion designer who is not much for action but can still kick some flank when the situation calls for it. G3 Fluttershy was a photographer (her name is a pun on "shutterfly"), and G4 Fluttershy may be a Shrinking Violet, but she has proven capable of feats like shaming dragons into submission, overpowering a cockatrice'sEvil Eye, standing up to a Mad God and eventually befriending him, and flying into a rage like you wouldn't believe.
The original Tirek was no pushover by a long shot, in the original Vile Villain, Saccharine Show, but his main threat was being the wielder of the Rainbow of Darkness and having an army whom he mutated with it at his command. LordTirek? He has no army nor Rainbow of Darkness, and is still such a massive threat that sending Discord after him is considered the best means of defeating him. Somewhat played with, though — he starts out far weaker than G1 Tirek due to his imprisonment, and Discord was sent out because his abilities let him sense Tirek's magic and track him down effortlessly. It's only after he drains enough ponies that he becomes a real threat. But once he gets going, there's no stopping him - he is able to duel Twilight Sparkle (who is wielding the power of fouralicorns) to a standstill, and that's not even the highest power level he reaches in the episode. Celestia has all but stated that Tirek could potentially become virtually omnipotent in Equestria.
From the same series, Grimbor & Terra-Man. The former in the comics was just chain-weapon themed villain who sought revenge for his wife's death, while the cartoon one was a skilled mercenary who owned the team (sans Karate Kid). The latter was originally a environmental terrorist who dressed in a cowboy-inspired battlesuit (and was exclusively a Superman foe, no less), while the cartoon version was a Terminator-like robot who was nearly unbeatable.
In the original cartoon, the Rat King is a man who had a connection with rats with speaking to them, but he usually left the fighting to his partner Leatherhead and was quite cowardly. In Teenage Mutant Ninja Turtles (2012), he gains Psychic Powers and becomes a Woobie, Destroyer of Worlds as Dr. Victor Falco, being able to easily telegraph the Turtles' moves in combat and having a mind link to the rats, manipulating Splinter on a much higher level than he did in the 1987 cartoon. It forces the Turtles to "fight without thinking" on their first encounter (something difficult for resident Smart Guy Donatello).
The Shredder does this on multiple levels. In the original comics, he was the Token Motivational Nemesis. Like the burglar that killed Spider-Man's uncle or the thug that killed Batman's parents, his role in Splinter's tragic backstory led him to train the Turtles. Shredder's first encounter with the Turtles ends in his death. The cartoons... not so much. The comedic 80s version treated him as a comedic 80s villain and so he's not thought of as too Badass nowadays, but his role in the cartoon is the titanic step up from "that guy who died in the premiere" to "Big Bad of the whole series, and often only beaten by the skin of the turtles' teeth, and always escapes to menace them and the world another day."
The other level is this: the later cartoons are more serious than the 80s one, so we go from cartoon villain antics to a deadly dangerous fighter and Diabolical Mastermind who has absolutely no trouble handing the Turtles their shells in early encounters and never becomes a routine, easily beaten foe. Learning of his involvement in a situation never fails to elicit an Oh Crap! from Splinter. (Also, specific to the 2003 series, he is almost supernatural in his unkillability, allowing him to show himself as Badass in defeat as in victory. Specific to the 2012 series, which is less serious than the 2003 one (but more than the 1987 one) Shredder takes the role that Slade does in the Teen Titans cartoon: he's the Knight of Cerebus for episodes that forget it's supposed to be a lighter series.)
April has usually been a Damsel in Distress in the older cartoons, only showing "badass" qualities on the sidelines. In the 2012 version, however, she's taken actual training as a Kunoichi, and most recently, was able to defeat Raphael in a sparing match. (Ralph keeps insisting she's "almost fully trained", although that really only means she hasn't completed the course.)
The Fantastic Four (1967) has a minor example. In the original comics, Sue seemed pretty worthless as a crimefighter until the writers expanded her powers from simply turning herself invisible, to also creating invisible force fields and turning other people and things invisible. This cartoon had Sue also use those abilities in retellings of early comics, so that she wouldn't seem too useless.
The cartoon did this with Whiplash, prior to his movie incarnation, where he goes from a loser in stupid costume with whip weapons to a cyborg in Powered Armor, who notably in the second season after a Mid-Season Upgrade defeats both Iron Man and Warmachine and destroys Iron Man's original armor. Also done with Justin Hammer, a Non-Action Big Bad in the comics, who in this series has his own armor as Titanium Man.
All of his villains get an upgrade, as there's something of an arms race between Tony and the Big Bads. Most enemies are in armor designed to try and outdo or replicate some of the powers of Stark armor, similar to the first two films.
Everyone in Star Wars: Clone Wars got a huge boost to their power level and their competency in a lost of places, the most spectacular being Mace Windu (who is already one of the most Badass Jedi ever) slaughtering a droid army with his bare hands. Indeed the spectacular destruction committed by the cast is so at odds with most Star Wars "canon" that it's a widely accepted Wild Mass Guess the series is in-universe propaganda.
Oddly enough, done with Warmonger in Mighty Max. Warmonger had only one appearance in the toyline the show was based off of, the playset "Mighty Max Trapped In Skull Mountain." In the corresponding mini-comic Warmonger is depicted as an ineffectual minor villain whose only accomplishment of note was getting splattered by friendly fire from Skullmaster's catapult. In the cartoon, he's The Dragon to Skullmaster and a capable villain in his own right, who's even managed to stand his ground against resident Badass Norman a time or two.
In the cartoon, unlike in the game, Pharaoh Man can punch you in the face.
Roll shows us how dangerous kitchen utensils are, and occasionally wields things like axes and buzzsaws.
Stinkor was created as a gimmick toy (the action figure had a stinky scent) and the character never appeared in the original cartoon because he was deemed too ridiculous (and given some of the characters who did make it, that's saying something). The reboot cartoon showed just how much a threat Stinkor could be. If it weren't for the fact he wasn't immune to his own scent, the guy would be nearly unbeatable.
Ivanhoe The Kings Knight portrays Ivanhoe as a bit more capable of a warrior since he had never received as grievous a wound as his literary counterpart had at any point in the series.