Toph, who is not blind, but merely incapable of seeing anyone less awesome than she is, and Iroh, who was not pulling himself up while training in prison, he was pushing the Fire Nation down.
Wang Fire. Don't you even dare suggest that he is the bearded alter ego of Sokka. The giant drill used to attack Ba Sing Se was originally built as a 1/8th scale model of Wang Fire's Wang. Which is acknowledged in a mini-comic about Sokka infiltrating the Fire Nation military using that name. It ended with him pretending to be killed while taking out a waterbender and earthbender, and being remembered as a hero. The Avatar has to deal with one firebender. Private Wang Fire◊ has to deal with therest.
Sokka often has fans exaggerate his intelligence from "competent strategist and inventor" to "rivals Ozymandias." Since he took out a fleet of war balloons with just two other fighters and invented both dirigibles and submersibles, he could be a realistic Ozymandias — capable of repeated moments of inventive and strategic genius, but still only human. Einstein didn't discover relativity every day. Considering Leonardo Da Vinci only theorized this kind of thing, whereas Sokka not only came up with the concept but designed functional units, and, in the case of the submersables, put the design into practice for the first time the week they would be used for an invasion, calling him an engineering genius may be understating it. Okay, he started out as a "competent strategist and inventor", but after he Took a Level in Badass he became the Steam PunkOzymandias.
The Mechanist designed and built the first war balloon; Sokka merely helped him with a design flaw, and Fire Nation engineers turned it from that into the massive airships we see in season 3. As for the submersible, Sokka merely came up with the idea. It was the Machinist who made it work.
From a single screenshot from "The Invasion", featuring Katara with an oddly disquieting look on her face where she seems to be staring directly at the camera, there has arisen "Creepy Katara". Apparently, it is impossible to look at her for very long without being creeped out. And she is everywhere. (Not surprisingly, she's also about two turns from Memetic Molester.)
Lin Beifong, much like her mother Toph Beifong, has achieved this due to stealing the show in every fight scene she's in. Her Heroic Sacrifice has only further fueled her Memetic Badassery and strangely has also increased her mother's.
KYOSHI. Ironically enough, she has only appeared in the opening of the show so far (though we did see her badassery in the last series), but it is universal fanon that she is constantly advising Korra to bathe in the blood and tears of her enemies.
Amon. Even before the series started, he was considered a badass by the fans. The fact that he became a Magnificent Bastard in record time and resisted the effects of bloodbending have only fueled this further.
Edd can make a candy-hunting satellite out of cardboard, rubber bands, and a tube of toothpaste.
Gaston from Beauty and the Beast. Because no one fights like Gaston, and no one hunts like Gaston, etc. Lampshaded in House of Mouse where they have a Running Gag of him butting in on other characters' conversations to say "No one [does what you're talking about] like Gaston!" (Actually, that episode might have been the inspiration for Gaston's meme.) In one episode, in which Clarabelle is gathering gossip, Gaston begrudgingly concedes that he has, indeed, seen others hunt like Gaston. There's also the Gaston Reads meme on dA. And at least one Take That as well. No one can get eaten like Gaston!
No one fires a flintlock three times without reloading... like Gaston.
He was forced to avert his meme once, though - in which someone mentioned shutting up, he states "No one shuts up like... nevermind."
Billy from Adventure Time is an in-universe example who crept into real life thanks to his absurdly memetic song. "Who's the greatest warrior ever, a hero of renown? Who slayed an evil ocean? Who cast the Lich King down? Billy! And that time the evil Fire Count captured a damsel fair, who saved her with such bravery that she offered him her hair? Billy! Also...He fought a beeeeeaaaaarrrr! Billy!"
The Venture Bros.. Brock Sampson. BROCK SAMPSON. A short list:Survived at least 50 poison darts and woke up with a minion still in his death grip, survived in space without a space suit, slept with thousands of women(Okay this parts a bit exaggerated, but not by much, only three people have fought him and lived over the course of the show, killed the dog reincarnation of Hitler, along with at least 200+ plus people(and that's just on screen), served in the military and two separate super-spy, lead a group of rag-tag henchman to take on an army of advance super-villlan helicopters, and to top it all off his greatest disire isn't peace or any of that crap:He fights cowboys riding on T-Rexes, Ninjas, and scubamen on motor cycles with Polar Bears in the sidecar. Brock Sampson is Bad Ass personified. When removing a bullet from him, super-villan Phantom Limb also found three more bullets, a blowgun dart, two shark's teeth, a tip of a bayonet, a twisted paperclip, and a meager handful of buckshot.
She's had this from the very beginning. Friend to All Living Things or not, it takes guts to fearlessly confront a rampaging manticore. Other notable creature-related instances include "The Stare Master", where Fluttershy manages a Death Glare that lets her outstare a cockatrice, and "It's About Time," where she effortlessly subdues Cerberus.
It's not all about animals, either. In "The Return of Harmony," she manages to outfly Rainbow Dash and shrugs off the Big Bad's attempts at More than Mind Control, which were effective on the rest of the cast.
And in Season 3 she gets said Big Bad to make a (sorta) Heel-Face Turn. As of Season 4, she is actually the only thing that keeps him under control, and he's a nigh-omnipotent Reality Warper! Fluttershy definitely deserves her reputation.
In-universe example in the form of Iron Will, a tough-guy motivational speaker who constantly refers to himself in the third person and even borrows phrases from Mr. T. He's gotten a bit of this out-of-universe as well.
Owlowiscious: he took on a frickin dragon!
Their names are so important they can't be held to just one syllable. They face down opponents, be it cockatrice, manticore or Discord without breaking a sweat. Princess Celestia has a cutie mark of them. They are the most interesting ponies in the world.
Zecora is a zebra who thinks that life is just too easy. She doesn't just travel abroad, she moves to a country where the residents have barely even heard of zebras. She learns a second language, then masters it so thoroughly that she phrases everything in rhyme just to make it harder on herself. And before she even knew the residents were afraid of her, she voluntarily chose to live in the monster-infested hellhole that is the nearby forest, because she doesn't truly feel alive unless there's a creeper staring at her through her front door every morning.
-So, basically, Zecora is one of those gamers who insist on always playing at the highest difficulty level. And her game...is life.
American Dad! featured an episode in which Stan tried to teach Steve to stand up for himself by acting like (more of) a tremendous jackass. He was trying to teach Steve to "get the oranges up the stairs" through hard work, but Steve decided it would be easier to pay Stan's old bully, Stelio Kontos, to kick the everloving crap out of him. It was made meme-tastic due to the catchy chant of, Stelio! Stelio Kontos!. Watch it here.
Stan: They're up the stairs! For the love of God, you got the oranges up the stairs!