Karai, born as Hamato Miwa, is the antagonist-turned-protagonist in the 2012 Teenage Mutant Ninja Turtles TV series. She is the biological daughter of Master Splinter (Hamato Yoshi) and Tang Shen. Karai is the older adoptive sister of Leonardo, Raphael, Donatello, and Michelangelo. She previously served as a highly decorated, but yet rebellious member of the fearsome Foot Clan in addition to being a skilled kunoichi (female ninja).
In her debut episode, "New Girl in Town", she tries tempting Leonardo to be more like her, while Leo wants her to see she's not as bad as she appears. Karai confronts Leo, who is separated from his brothers when he and Raphael have a heated argument over who should be their leader. During their first battle, she temporarily blinds him before attacking him. However, she leaves him alive. She later runs into him again in an alley and duels him again. They both exchange some witty (and flirtatious) banter and some non-fatal blows until Karai holds a sword against Leo's neck, trying to convince him that he's giving him any more information other than she wants to show he's not as good as he appears. She also notes during her duel with Leonardo that she understands the Shredder's revenge, but she's uninterested. And that, she jokingly stated, he (the Shredder) should get a hobby. She tells Leo to meet her at the top of a building to show him something. At midnight, Leo meets Karai on top of the building she informed him about earlier. She tells him that they're there to steal a famous katana, which is clearly visible in a museum window down below. Leo refuses to help her which upsets her. Before she takes out her katana, Leo stops her and tells her that he believes that there's good inside her. In disbelief Karai betrays Leo by using his feelings for her against him. She violently knocks Leo to the ground, pinning him down. Raphael then shows up, and is angry at him for "holding hands with the Foot." Upon Snakeweed's attack, she just stood there, until Leo begs for her help. She flings her knife towards Leo's face, and it lands on the wall very close to his head. Leo uses it to cut himself free, and he and Raph successfully freeze Snakeweed and smash his frozen corpse to bits. Whether this action by Karai was to help Leo or harm him is unknown, however, Karai did snicker and slip away, implying that she held her little scheme.
Karai meets with The Shredder, who is not happy that she let Leo live. It is implied that Karai may have had feelings for Leo by sparing him and lying about it, as she tries to talk her way out of it and say that he escaped, but Shredder doesn't believe her. He unsheathes his claws, forcing her that she must kill him next time, or else... Their scene ends with Karai reluctantly obeying and calling him "father" (a shockingly intriguing moment, implying that she is most likely Shredder's "daughter") as she becomes frightened after making The Shredder angry at one of her comments.
In "The Alien Agenda", Karai finds the Turtles fighting the Kraang. She becomes somewhat concerned over The Kraang, yet intrigued. When she informs The Shredder of this, she tries to convince him to take some concern over them, due to the mutations that happened to the Turtles, Xever Montes and Chris Bradford. Shredder believes that this is all nonsense, and dismisses her suggestions. She becomes relatively disappointed that her Shredder has no interest or concern over The Kraang. Shredder then reminds his daughter of his reason for his ongoing vendetta against Splinter. To find out more about The Kraang, she questions Leonardo when the two happen to encounter each other on a rooftop, during which she mischievously duels and playfully flirts with him. But he refuses to tell her anything, warning her that the robots are dangerous, while also telling her to leave him and his brothers alone. Raphael asks Leonardo about her, and if they should tell the other two brothers about her and his "relationship", but Leonardo says that the two already had a 'chat' and confirmed that she's going to leave them alone. Raphael thinks that telling her to back off is a pointless idea. She keeps it to a point, as she followed the 4 brothers into The Worldwide Genome Project (which is actually run by The Kraang in secret) building, seemingly undetected. However, when the Turtles realize that Raph was missing, he has found Karai and pins her down. The two fight, but it's not long before Leonardo breaks up the skirmish. When Raph makes a comment, Leonardo argues that Karai is good, while Raphael thinks she's pure evil, while Michelangelo and Donatello are confused by who she even is. The fight gathers The Kraang's attention, and they attempt to subdue them. Karai makes the fight worse by recklessly, yet deliberately and malevolently unleashing a monster containing DNA from assorted animals. She then grabs a broken Kraang droid, and selfishly abandons the Turtles, and brings it to her "father" to possibly convince him that The Kraang are worthy of looking into. Also, Baxter Stockman claims that he could work with the technology efficiently. The Shredder's mindset has successfully been changed, and he asks her to find out everything she can about the Kraang.
In "Enemy of My Enemy", Karai appears out of nowhere while the Turtles are surveying the T.C.R.I. building. She immediately pulls out her katana and attacks Leo, Raph, Donnie, and Mikey all join in to fight her, but she quickly begins to outmatch them. She mentions that she overheard Donnie talking about The Kraang. At first, they don't want to let her in on the situation, but Raph lets lose that they are trying to stop a full-scale invasion. Suddenly, a flash of purple light comes from the T.C.R.I. building. A door opens on a side of the skyscraper, and a strange aircraft floats out, resembling a jellyfish, with a round body, three short, stubby tentacles and a single purple "eye". It is piloted by two Kraang brains, who quickly spot the turtles and Karai and move in to attack. The ninjas run across the rooftops, narrowly avoiding the ship's energy beam weapon. Karai ducks into an alley, while the ship pursues the turtles. Leo runs out to draw the ship's fire, while the other three make it to the sewers. Leo joins them and they watch the ship from a storm drain. The ship activates a cloaking device and vanishes to avoid detection by a passing Police helicopter. Karai returns to The Foot's headquarters and reports what she has seen to The Shredder. He ignores the threat that The Kraang pose, and tells her that they will soon receive a shipment of new weapons that will end their war with the turtles and Splinter. Later, after a brief, yet playful spar with Leonardo, she tells him that she wants to help them fight The Kraang. She is afraid that Shredder's stubborn refusal to see anything beyond his vengeance will get them all into big trouble. She asks him if they could work together, but Leo refuses and leaves. Later, the ship chases the Shellraiser down a street. Leo asks Mikey for an escape route and Mikey accidentally leads them into a dead end. The ship starts to blast through the Shellraiser, but they turtles narrowly avoid definite annihilation by backing out of the alley quickly and hitting the streets once again. Karai then jumps out of nowhere onto the top of the ship and effortlessly, begins slamming her katana on it. Leo decides to help her out, and he jumps into The Shell Cycle and chases her and the ship down on his own. When Karai falls off of the ship, Leo saves her at the last possible second. He then brings her into The Shellraiser. When Raph instantaneously objects to her presence, Leo tells him to hear her out. Karai tells them that they need her help and that the only way to take that ship down is with a missile launcher from the Foot shipment, which she tells them will be arriving at the docks the next evening. All of the turtles except Leo are suspicious of her, so Karai says that she will get the missile launcher herself. Leo agrees that, if she gets the weapon, the turtles will team up with her to stop the ship. Secretly, however, the turtles devise a plan to eliminate The Shredder, as he would never be expecting them to show up there. As Karai retrieves the missile launcher, she spots the turtles on top of a shipping container near the docks. She pushes Shredder out of the way so that the electric grenade (which Donnie invented) electrocutes the Foot Soldiers and the man with the diamond eye (who was the one who brought the shipment). Karai then fires at the turtles, knocking them off the container. Leo makes it to the box of missile launchers, but is confronted by Karai. She tells him that she feels betrayed and that he is just as short-sighted and obsessed as The Shredder. She then reveals to Leo that The Shredder is her "father" (apparently). Leo is shocked by this news. Karai says that the deal is off and violently attacks Leo. After a short fight the ship returns and Karai hides from it. When she emerges, she finds that Leo has already taken a missile launcher and gone after the ship. Meanwhile, the other three turtles are fighting against The Shredder, but are miserably losing (much like the prior time). Meanwhile, Leo takes aim and fires a missile at the ship. The missile hits its target and the ship crashes into the wharf, knocking Shredder into the ocean. Karai dives in after him, while the turtles retreat. Karai helps The Shredder out of the water. He thanks her, and tells her that he has found a pet for her and holds up a Kraang, which he has captured.
In "Karai's Vendetta", Shredder's interrogation of the captive Kraang proves futile, as it does nothing but senseless squealing. Karai suggests putting the Kraang into the limbless exo-suit they possess. Upon hearing it speaking relatively sensible english, the Kraang stated that they hunt the turtles because the latter protect April O'Neil, who is crucial to their plans. Thus, Shredder dispatches Karai to capture April to draw the turtles out. She meets April under the alias "Harmony". She then reveals her identity when trying to feed April turtle soup. April forces Karai to pursue her on foot, but she traps herself in an alley. She pulls out her weapon and Karai compliments on it before disarming her. April tries attacking her directly, but Karai dodges her attacks and starts attacking her, easily overpowering her. She knocks her into the street and demands to know why she's so important as she continues attacking her. April is able to defend herself and provide her own questions. However, just when Karai has her pinned, she mentions losing her mother, causing Karai to hesitate which distracts her long enough for April to throw her down the subway stairs and escape.
In "Showdown, Part 1", Karai leads a squad of foot soldiers into the sewers, where they abduct April after she is led away from the Turtles' lair by her brainwashed father, Kirby O'Neil. she then helps lead the Foot to the surface where they hand April over to the Kraang.
Later in "Showdown, Part 2", Karai intervenes in Shredder and Splinter's battle just as Splinter is about to kill her "father". Prior to this, Shredder had revealed to Splinter that after their last battle, fifteen years ago, he had taken Splinter's daughter, Miwa, and raised her as his own. Splinter recognizes Karai as Miwa during their brief confrontation, and when Shredder informs her that the rat is Hamato Yoshi, Karai accuses Splinter of murdering her mother, another lie told to her by the Shredder. She attacks Splinter, but her true father refuses to fight her, and leaves the lair upset on what the Shredder has done to his daughter.
In "The Mutation Situation" (which also marks her first non-speaking role in the series), she walks up to the Shredder's throne while he puts his helmet on. She then sets up a projection screen that was recently provided by the Kraang. The Kraang then inform them that their mutagen shipment is ready and is on it's way to them [as they plan to use it to build an army of mutants to destroy splinter and the turtles]. They then inform them that they have a secret weapon that will combat any interferences; a large foot of some kind of ape creature then appears on the screen. After a while, the shredder asks the Kraang where is shipment is. The Kraang then informs him that the turtles have either destroyed or sent their ship off-course to which they state that they will somehow make amends. The Shredder then tells Karai that the Kraang have become useless and that he will clearly have to expand his army on his own.
In "Follow the Leader", she becomes very interested in the Turtles hunt for the dozens of mutagen canisters scattered across NYC and forms a plan to trap them. She is later seen looking at a torn photograph of her late mother when she is ambushed the new Footbots, a latest invention of the Kraang for Oroku Saki. Although overpowered by their impressive fighting techniques, Shredder emerges to inform her that he is leaving for Japan to take care of "urgent business." He warns her not to make any moves against the Turtles until his return to New York, that obedience comes with a stiff penalty. Karai is set upon by robotic Foot ninja , which were designed by the Kraang to adapt to their opponent's moves. When she was at the robots' mercy, Shredder intervenes. Karai asks if he was going to let the Foot Bots kill, to which he doesn't answer. Shredder then says he's leaving for Japan on business and warned her not to make any moves against the Turtles. But she disobeys him, seizes and captures Leo, abducting him to Bradford's dojo. While having him in her custody, she intimidates him in several ways: threatening to expose his existence to the human society so she can make a fortune; taunting and humiliating him by vengefully and malevolently ranting that Leo deserves everything he's getting before ruthlessly coercing him to battle the Footbots. When his brothers rescue him and escape, Karai catches up with Leo and nearly pushes him off of a building. However, Leo avoids falling by sticking his katana into the ledge, and he jumps behind Karai, catching her unaware. She falls to the ground, where Leo holds a sword to her head and tells her that Shredder is lying to her and that Splinter did not kill her mother, while also ordering her to stay away from his brothers and keep the feud between her and him. As he leaves, he gives one last plea for Karai to believe him about Splinter. Despite all this, Karai is still suspicious and angry at Leo about Splinter and doesn't look threatened by Leo's orders. She also glares at Leo, who escapes to safety with his brothers, implying that she will continue to come after them.
In "Mikey Gets Shellacne", Karai dispatches Dogpound and Fishface to find Baxter Stockman so he can maintain her Foot Bots. She later finds her two subordinates, Dogpound mutated into Rahzar, in Baxter's old lab and tells the good doctor that he works for her and the Shredder.
In "Target: April O'Neil", Shredder is very unhappy that Karai disobeyed him and sought out the Turtles. Karai blamed her failure on the Foot Bots but insists that the Kraang are improving them. However, Shredder orders to avoid any deals with the Kraang until his return. Again, Karai disobeys and goes to the Kraang, who are building a robotic replica of Bradford's old human form. She then decides on a test run on April. Though the Kraang become startled, they permit the test. Karai eventually confronts April and Donnie with a squad of Foot Bots. While her robots distracted Donnie, Karai engaged April, bragging that her years of training make her superior, only to be struck in the head by April's tessen. Despite this, she is able to incapacitate April, only for Donnie to come to her defense and knock her down instead. Just then, Bradford arrives and seizes April, it disobeys Karai's orders to kill her as it obeys its Kraang programming to kidnap her for the Kraang. Karai stopped it from taking off with her rival, causing the robot to turn on her. When the other Turtles arrive on the scene, Leo assists April to use the smoke bomb to escape.
In "The Manhattan Project, Part 1", Leonardo genuinely tells her that Splinter is her real father, but she refuses to accept it and thought it was a lie. The Shredder returns from Japan with his new recruit Tiger Claw his new second-in-command. Karai got upset and felt threatened because she earned that job of being second in command. She then mocked Tiger Claw’s appearance. Shredder then tells Karai to treat Tiger Claw with the upmost respect and to do as she’s told. She then assists Tiger Claw in capturing Splinter and bringing him to Shredder by using the Turtles as bait. Meanwhile Karai is showing and practicing the honor that Shredder had taught her about over the years. With Splinter captured, chained and weakened by poison, Karai got the opportunity to show her honor side. She refuses to let Shredder slay Splinter as she rather see Splinter die through a fight not when Splinter is chained. Splinter was happy and asked why Karai had helped him. Karai thought he looked “pathetic“.
In "The Manhattan Project, Part 2", after the defeat of Tiger Claw, Raph then wonders where Karai is now. Meanwhile April still cannot believe that Karai an “evil witch” is Splinter's very daughter. Splinter states that one day Karai will accept the truth, but that is her decision to make alone. Little do they all know, Karai is hiding behind another billboard on the rooftops nearby, overhearing everything that they said. Based on her several facial expressions, Karai started to her reflect on what is going on. Not only Karai is in a difficult situation, but she finally starts to question herself, whether or not Shredder is telling the truth.
In "The Wrath of Tiger Claw", Karai was shown sadly looking at a photo of her mother (while having a flashback of Leo genuinely informing the truth). Karai is still confused and wants to understand what‘s going on. When The Shredder asked her what was bothering her she then told him she wanted the truth about her mother; Shredder then told her that Hamato Yoshi killed her. All is interrupted when Tiger Claw returns; Karai questions how he possibly could've survived, Tiger Claw explains how he escaped and all the battles he's been through and how he wants revenge on everyone who made him go through it. Shredder then tells him that he will grant his wish and orders Karai to go with him and destroy the turtles and Splinter, much to Karai's dismay. She is initially reluctant, but after Shredder pressures her, Karai obeys, but at the same time she wants to investigate first. While running through the rooftops and bantering she questions Tiger Claw on what his plan is. Tiger Claw then tells her that she is with him because she knows where the turtles hang out and who their friends are. They head off to Murakami's restaurant where they torture information out of him. Karai sees how scared he is, states that there is no honor in what they are doing and turns away. Tiger Claw, having no such moral objections, trashes the place and gains information on the turtle's friends. They then go to the movie theater and find Casey, April and Irma there; April senses them and then they split up to separate them. Karai catches up with April, who prepares for a fight but Karai tells her she just wants to talk and tells her about her conflicted emotions: all her childhood she was raised believing that Shredder is her father while Splinter is the enemy, so when Leo told her the truth about Splinter, she couldn't believe it at first, and how the Shredder lied to her and that now she believes Splinter is her father. Karai is caught in the middle alright, but she isn’t actually sure if Splinter is her father. Karai is only there to investigate on whether or not she should still believe Shredder before making any judgement against the Turtles. Donatello and Leonardo arrive and she tells them the same. Karai tells Leo that she now believes him about Splinter. Once again, Leo has no idea that Karai is only there to investigate the truth before making any judgement. Overjoyed, Leo takes her to the lair to see Master Splinter, much to Raphael's dismay. Once there, Raph angrily argues with Leo and Donnie, remaining suspicious of her motives, suspecting that Karai might be leading Shredder to the lair. During the argument, Karai secretly tracks Tiger Claw just in case if the “truth“ is actually a trap. Splinter enters the room and stops the argument. Then he sees Karai or Miwa in his eyes, and he tells her to come with him as he has something to show her. Karai followed Splinter. When Karai saw the dojo, she becomes fascinated by the beautiful sight. He then shows her photographs of himself as a man, Tang Shen, and baby Miwa all together. Seeing this, she finally realizes the truth is real. She’s very upset on how many years the Shredder has been lying to She regretted tracking Tiger Claw. Thinking fast, Karai genuinely joins forces with the Turtles as they race out of the lair across the underground sewer tunnels to lead Tiger Claw away, but not before Splinter advises Karai to be who she chooses to be. As they are on the run, Karai doesn't know where to go since this all looks like a maze, but Michelangelo does. Mikey leads the team (who leads Tiger Claw) to a far-off meat processing factory where the Turtles brawl against Tiger Claw. However, he proves too strong for all of them despite their best efforts and then offers Karai the "honor" to kill Leo. She refuses to kill Leo. Instead Karai attacks Tiger Claw but is unfortunately bested and knocked out by him and taken hostage. Tiger Claw threatens to throw her in the grinder if the turtles step forward, so they keep their distance and he gets away with Karai. Leo suggests they go after them, but they have no choose but to return to the lair after Mikey is revealed to be badly injured. Furthermore, Raphael think Shredder still loves Karai. Meanwhile at Shredder's hideout Karai demands the truth from him and Shredder finally, yet bluntly admits that Splinter is her true father. He then has her jailed in a dungeon, now that she knew the truth about her parentage and true clan.
In "The Legend of the Kuro Kabuto", she is seen in her cell trying to escape by clawing at the door using a miniature weapon. Suddenly the Shredder enters and comes to the opposite side of the door. He then tries to explain why she is with him and that it would have been wrong for her to have been raised by “scum“ like Splinter as well as the fact that everything he did was for them, the Foot and their honor. He then states that one day, he hopes that she will comprehend him for all of this. After he leaves, she continues to claw at the cell door hoping to escape very soon.
In "Vengeance is Mine", Fishface is delivering a bowl of food to Karai, who is still in the Dungeon. Karai admits that she hates the food she's being served, but Fishface angrily commands her to eat whatever he brings. Karai quickly corrects that it was Tiger Claw who asked him to bring the food. Disgruntled, Fishface tells her to not speak to him in that manner and then departs. However, after he does so, it is revealed that Karai has finished dismantling one of the cell bars, so she is able to separate it from the cell door and use it to bust open the door. Karai then runs to the Dungeon exit and easily picks the lock, only to find Tiger Claw blocking her path forward. Karai attempts to attack him with the cell bar, but Tiger Claw merely grabs it and bends it until it is useless. Karai nearly succeeds in striking her foe, but Tiger Claw pins her down instead. The Shredder then appears and orders Tiger Claw to spare Karai. Tiger Claw agrees and, later, Karai awakens with chains around both of her arms, while Shredder is standing behind her. Shredder takes off the lower part of his mask and asks why Karai has persisted in trying to turn against him. Karai refuses to speak, causing Shredder to ask why his daughter is not responding. Karai tells him that she is not Shredder's daughter. After her daring rescue by the Turtles, Leo asks Karai if she is willing to stay with them for quite a while. With Shredder going after them all, Karai says that she has no other choice and confesses that their lair is pretty nice. When Splinter arrives and sees her, Karai then goes over and hugs him, which causes Splinter to believe that some things might indeed be worth the risk. After a training session between the turtles, she glances at the picture of herself as an infant and then asks Splinter about the details of his and Shredder's rivalry. Splinter explains that their rivalry was even deeper than what occurred with Karai's mother. He tells her that the Hamato Clan and the Foot Clan were battling for centuries upon centuries. Oroku Saki was just a young child during the Hamato Clan's final attack, so splinter's father decided to give Saki shelter, and Oroku soon met Hamato Yoshi (Splinter). After that, the two children grew up alongside each other as brothers, and they rivaled one another with their impressive Ninjitsu skills. However, this rivalry only grew bitter when the two of them met Tang Shen for the first time. Not long after this, however, Saki learned about the clan that he truly belonged to (the Foot Clan) and was enraged at Splinter for not telling him. Because of this, he invaded Splinter's household and tried to kill him, but accidentally killed the beautiful Tang Shen instead. He blamed Splinter for everything, so he burned their home down and took Miwa away and rejoined the Foot Clan. Karai then asks her father why he has never sought out revenge, only for Splinter to explain that revenge is the thing that will always lead to more pain - something that the Shredder does not realize. He then says that being reunited with Karai is far better than anything. He then pours his daughter a glass of tea to drink. Soon, the four brothers are preparing to go to bed, and Karai appears to be asleep already. However, Karai then wakes up so she can leave to the lair to take Shredder down. Leo waits for her by the subway tracks and informs her going to the Shredder alone is dangerous, but he believes they should face and defeat the Shredder, as he will never stop hunting them. Then Karai walks towards him and puts her hand on his shoulder, she mumbles that she's sorry and then throws a ball of blinding powder in his face. She then departs down the subway tunnel, claiming that 'this will end tonight'. Breaking back into Shredder's headquarters, Karai sets her sights on destroying Shredder, but he has been expecting her return and has a trap well prepared. At Baxter Stockman's lab, Stockman finishes mixing some DNA for a new batch of mutation, only to drop some unknown solution into it, when the Shredder arrives with the foot and Karai, explaining that she would be used as bait in order to capture the turtles and mutate them into snakes to use against Splinter. When Splinter and the turtles attack, Leo manages to reach Karai, only for Shredder to swipe at him, missing him and cutting the chain, watching helplessly as Karai falls into the mutagen. Karai is mutated into a three-headed white snake and wraps herself around Splinter, thinking him to be food, but is reminded that he is her father, which causes her to slither away, and they all escape before the building blows. At the end of the episode, it is revealed that she has the ability to transform into a slightly serpentine version of her human form, which is no doubt due to the unknown substance that Stockman accidentally dropped in the DNA before adding it to the mutation.
Karai makes three brief cameos in the season 2 finale, "The Invasion". In the episode's beginning, Shredder has flashbacks of key moments in her life, including her training and mutation. Then, she appears shortly as Casey and Raphael are looking for her. Then, at the very end of "the second part", she saves Splinter from drowning, she kisses him, before slipping away into the water.
In "Serpent Hunt", the turtles search for her while she is being hunted by Ivan Steranko and Anton Zeck as well as Fishface and Rahzar who try to capture her on Shredder's orders. The turtles manage to track her down to an abandoned factory where they get attacked by the Kraang who she easily takes out. They then try to talk to her, where Donnie realizes she is becoming more snake-like. She then transforms into a human, where it's revealed her human form looks more pale and scaly than it did after she got mutated, and informs them that it's to dangerous to go with them. Fishface and Rahzar show up and manage to capture her by stunning her with a taser. Ivan and Anton then capture her and attempt to make a deal with the Shredder by handing her over to him so he can help them escape the city that the Kraang have taken over and constantly patrol everywhere. The turtles then show up and free her while they fight the shredder. She then gives them a clue; pointing to the East and the word "comet" before she escapes by jumping into the water at the docks.
In "The Pig and The Rhino". The Turtles, Casey, and April discover three potential places that Karai could be hiding and split up to find her with retro mutagen in an attempt to change her back. Leonardo and Michelangelo discover she's been at Coney Island and her hint regards the Comet Roller Coaster. Karai evades them in the Haunted House attraction but they corner her outside, where she almost attacks Mikey but is stopped by Leonardo. He asks her if she can change forms but it appears that she can't. She runs away once the now mutated Steranko and Zeck show up (who Mikey calls Bebop and Rocksteady). When Bebop and Rocksteady fight over the retro mutagen she appears and spits acid in Rocksteady's face, causing him to drop the retro mutagen and crush it as she escapes into the haunted house with Bebop following her. This distraction allowed Leo to free his brothers, April, and Casey. After the turtles defeat Bebop and Rocksteady, Karai comes out and Leonardo sprays retro mutagen on her, but to their disappointment it has no effect, as Donatello says that Karai is a special kind of mutant. Leonardo offers to bring Karai home, but she thinks it's too dangerous as her mind is still deteriorating. As it turns out, she only brought the turtles to the location so she can say good bye to all of them as she once again escapes into the water. Later, in the streets, she tries hunting a nearby rat, but it was a trap set up by Bebop and Rocksteady, who take her to Shredder's lair. Shredder swears that he will cure her and they will have their revenge on the Turtles, as Karai angrily hisses at him.
In "Casey Jones VS. The Underworld", Karai is seen imprisoned behind a glass wall in Shredder's Lair, banging on the wall for escape, as Shredder once again promises they will reverse her mutation.
In "The Noxious Avenger", she is briefly seen in her cage in Stockman-Fly's lab.
In "Clash of the Mutanimals", she is seen imprisoned in Shredder's lair, where she overhears Shredder's plans to use the mind control serum on her.
In "The Deadly Venom", Stockman-Fly successfully restores her human form and infected her brain with a Mind Controlling Worm. Shredder then orders her to attack Rocksteady who she defeats easily. Shredder then orders to hunt and destroy the turtles and their allies. She first sends a bunch of venomous snakes to bite April and then she got the drop on Casey Jones. He gave her a good fight but by using both her ninja skills and her new control over her mutant powers she over powered him and gave him a poisonous kiss. When Mikey and Raph came to save him Karai's snake came out of Casey's clothes and bit them. She then used all four of them as bait for Leo and Donnie and she placed some of her venom in the water they swam in. With Leo poisoned she quickly got the upper hand but by using a healing technique Splinter recently taught him, Leo beats her venom and defeated her, but when he turned his back for a minute she was gone.
In "Tale of the Yokai", she is seen as in infant with her mother Tang Shen. Her mom leaves her unattended to go after Splinter and Shredder. After her mother's unfortunate death, she is stolen by the Shredder who renames her Karai.
In "Attack of the Mega Shredder!", she is seen briefly being attached to some kind of contraption as she's forced to endure multiple worm injections due to the fact that one single mind-worm is not enough to keep her under the Shredder's control (most likely from her fight with Leo involving the Healing Hands technique in "The Deadly Venom"). The Shredder apologizes to her and promises her that they will soon have their revenge on Splinter and the Turtles. Bebop and Rocksteady are then assigned by the Shredder to watch over her as well as secure the base from the turtles.
In "The Fourfold Trap", she sets up a trap for the Turtles with Shredder's other henchmen to lure Splinter to her. She lures Donnie first by having Stockman hack into his T-Phone and making him think April is calling him. After that, she captures Mikey by luring him to Murakami's and having him eat pizza gyozas spiked with a chemical to knock him out. Finally, she lures Leo, Raph and April when she fakes a phone call from Mikey. When they arrive, they are quickly overwhelmed by Karai and the other mutant henchmen. Karai has the turtles placed in separate rooms each filled with a different trap, while April is chained near Karai. April then has no choice but to call Splinter and warn him, where Karai takes her phone and finally talks to Splinter, who is surprised to hear his daughter after so long. Splinter arrives where the Turtles are kept, and he defeats each and every one of Shredder's henchmen until only Karai is left. He tries to reach his daughter and pleads for her to stop, even calling her Miwa, but she doesn't listen and attacks him. During the fight, he tells her that he loved her mother very much, but this only infuriates her. Splinter dodges all of Karai's attacks and knocks her weapon out of her hand. He then says that he won't fight her. She reverts to her mutant form and says that he doesn't have a choice before lunging at him. Splinter narrowly avoids getting hurt by her as he tries to dodge her attacks, until she dives into the water around the command center. Splinter then takes Leo's suggestion about the healing mantra and goes through the motions as Karai circles him in the water. Just as she tries to attack him, he finishes the hand motions and hits her several times in crucial areas with the mantra. He then tells her he loves her before pressing two fingers into her head. She spits venom in his eyes, and wraps around him. Just as she is about to finish him, she screeches in pain as the brain worm that's controlling her weakens, causing her to let go of him. She thrashes in pain and throws herself off the platform until Splinter grabs her by her wrist. Unfortunately, her wrist slips out of his hand and she falls into the water as it drains into the sewer, taking her with it, much to Splinter's sadness. At the end, she lands in a sewer pipe and changes back to her human form. The healing mantra that Splinter performed on her is shown to have worked as she pukes the brain worm out of her mouth, thus restoring her free will and going back to normal.
In "City at War", after being freed from the brain worm, Karai calls her old friend, Shinigami, from Japan to aid her in taking down Shredder's criminal empire. When Shinigami returns to Karai at Shredder's old headquarters with a tanto carrying the Hamato Clan insignia, they soon are confronted by April and the Turtles, as the tanto belonged to April. Karai explains that she's no longer their enemy now that she's free of the brain worm, and explains her plans to rebuild the Foot before Shredder's corruption, take down his criminal empire, then Shredder himself, once and for all. The Turtles offer their support, but Karai believes she needs to do this herself. However, she does allow April to face Shinigami again for getting her tanto back. Though Shinigami easily beats April, Karai agrees to return the tanto, before the Turtles and April then take their leave. Later, Karai and Shinigami arrive at a martial arts store that Karai knows is a front for Shredder as he keeps a cache of weapons in the back. They are soon attacked by Tiger Claw, Fishface, and Rahzar, and before surrendering after Tiger Claw takes Shinigami hostage, Karai sends a text message for help to the Turtles. After being subdued, Karai frees herself, but is soon overpowered by Tiger Claw, who prepares to kill her before the Turtles and April arrive to help after getting Karai's text message. As Karai and Leo fight Tiger Claw, at one point, Karai allows her mutant self to surface as she turns her arms into their mutant form to attack Tiger Claw with, but he is still able to overpower her before April incapacitates him with The Dragon's Tail, allowing Karai and Shinigami to escape with the Turtles and April, but not without leaving behind enough explosives to wipe out the weapons cache for Karai. Back at the Turtles' lair, Karai speaks to Splinter about what she's doing, and though he wants her to join the Turtles and work together with them, Karai explains that she's grown up now and needs to deal with Shredder in her own way. Splinter voices how proud she is of her as she departs with Shinigami to continue her plans with rebuilding the Foot and wiping out Shredder's empire, not realizing that she may have started a war with Shredder that's she's not going to win.
In "Broken Foot", Karai and Shinigami are aided by Leo behind Splinter's back as they continue to systematically take down Shredder's criminal empire, taking down Hun and his Purple Dragons before burning a temple full of Shredder's laundered money, then attacking Auman Chemicals, encountering resistance in the form of Foot-bots, Tiger Claw, Bebop, and Rocksteady, but managing to plant their explosives and damage the facility, aided by fresh Foot Ninja from Japan. However, Donnie was injured trying to save Mikey and Raph from the explosion, and as a result, Karai and Shini are forced to flee from Tiger Claw before he goes after the Turtles with Bebop and Rocksteady. When Leo arrives at Shredder's old lair with Mikey and Raph, Karai reveals her next target to be the Foot-bot manufacturing facility at Auman Chemicals. Destroying it would cripple Shredder's army beyond repair, but having witnessed what Karai's revenge did to Donnie, Leo wants nothing to do with it, leaving Karai to blind him and his brothers, while Shini uses her magic tricks to further disorient them so Karai can take Shini and the Foot Ninja to still take down the factory. However, their plan falls apart due to Tiger Claw, Bebop, and Rocksteady anticipating their arrival and having the factory crank out Elite Footbots, which manage to overpower Karai, Shini, and the Foot Ninja, capturing them. However, Leo, Raph, and Mikey arrive to save Karai and the others, but thanks to Raph fiddling with the control panel, the Turtles, Shini, and the Foot Ninja are sorely outnumbered by Elite Foot-bots, until Karai plants an explosive on the large cistern at the top of the factory and detonates it manually, burning the side of her face, but causing the cistern to plunge into the molten slag below, splashing it on the Elite Foot-bots and destroying all of them along with the factory. Leo retrieves Karai, and together with Mikey, Raph, the Foot Ninja, and Shinigami, they escape as the NYPD flood to the factory, now a raging inferno, regrouping in an alley where Karai uses her mutant abilities to heal her burn wounds similar to a snake shedding it's skin, much to the Turtles' amazement before they return to their sewer lair. Once there, while the Turtles are overjoyed to see Donnie fully healed thanks to Splinter's healing mantras, Karai apologizes to Splinter for having allowed her revenge to bring harm to others. She then decides that taking down Shredder's criminal empire is no longer her priority. As of now, she's going to go after the Shredder himself, turning to leave and drawing her tanto blade as she does.
In "The Insecta Trifecta", Karai has ordered to her Ninjas to look for Shredder, only for them to report negative results, angering her and assuming her half-mutant form as a result before ordering her Ninjas to leave. Right after that, she notices Stockman's Antrax servant invading the lair before Stockman himself and Scumbug arrive. She says of all the mutants Shredder would send to take her down, he just sends his only and useless bug, much to Baxter's infuriation, and manages to put a good fight against Stockman's minions before she is caught in a spider web. The Turtles and April arrive just in time to save her but the group is overpowered by Stocman and his minions' ability to fly and one more hallucination of Raphael's is enpugh for Karai to be taken along with Leonardo and April. She is seen trapped in a spider web along with Leo, April and Casey (who was captured as well before her) in a high-rise construction and worries if Stockman and his minions are going to eat them. She is rescued by Mikey, Donnie and Raph and teams up with April to defeat Stockman's minions before she kicks Stockman out of the controls of a crane. The team captures the mutated scientist's minions while he flies away back to his master's mansion
In "The Super Shredder", Karai is at her base when a blackout occurs. When Shinigami reports she has no idea how it happened, Karai suggests doubling the guards outside, only for Tiger Claw and Rahzar to enter. Karai is ready to fight them, when they reveal Shredder is with them, entering to reveal he's become what Karai says he hated the most: A mutant. Shredder manages to take out Shinigami, their Foot Ninja, and Karai, in her mutant form, before threatening to hunt down Shinigami if Karai does not surrender to him. Left with no choice, Karai surrenders, and watches as when the Turtles and April arrive in the Shellraiser to save her, Shredder easily overpowers the Shellraiser and sets it ablaze, much to Karai's horror.
Afterwards, Karai is taken to be held hostage in the area where Shredder and Splinter had their last battle that Shredder won. When Splinter arrives to save her, he is confronted by Shredder, and soon forced to retreat when he realizes he's no match for Shredder in his mutated state. As Splinter lures Shredder away, Karai frees herself and regroups with the Turtles and April, only to be stopped from pursuing Shredder and Splinter by Elite Footbots. By the time they reach Splinter and Shredder in the under-city where Splinter fought the Rat King, they are unable to help as more Elite Footbots block them from reaching Splinter, who manages to collapse the broken bridge segment he and Shredder are on, before dragging Shredder with him to their presumed deaths. As the Elite Footbots begin to rain arrows on them, Karai, April, and the Turtles are forced to retreat and regroup, knowing that Splinter might still be alive if he survived the fall. Before they can consider it further, the doors they were hiding behind are blown open, and they find themselves confronted by Bebop, Rocksteady, and at least a half-dozen Elite Footbots...
In "Darkest Plight", Karai encourages the team to take down Bebop, Rocksteady and the Elite FootBots for Splinter, but they retreat due to being severely outnumbered. April called Casey to help them search for Master Splinter. While Donnie, Mikey, Raph and Casey search in the abyss of the under-city, Karai, Leo and April are going to watch for Shredder and his goons. April senses Shredder and Tiger Claw's presence and Shredder orders his loyal bounty hunter to destroy April, bring Karai to him alive, and also Leonardo so Shredder could destroy him personally.
Tiger Claw follows the trio to a roof, knocks Leo off the roof into a street and almost kills April but Karai protects her fellow Kunoichi, leads the mutant tiger away from her and defeats him using her serpent form's tail to throw him into some power lines, electrocuting him knocking him out for a while. She and April save Leo just in time from being crushed to death in the hands of the Super Shredder. After Shredder is hit by a truck, he lifts it and throws it right to Karai, but she's saved by April, aided by her Soul Star crystal, which gives her the strength to throw telekinetically the truck right back at Shredder. But Shredder catches Leo and prepares to finish him off, only for Karai to beg him to do not do this as he could do something good for once in his life than wasting it with revenge. Shredder gets touched by this, but Karai was just using this to give Leo time to escape. Karai then screams at him, saying he was never her father, and punches him right in his mutated pulsing heart, which causes him to spill mutagen from his mouth and limp away, severely weakened. Karai prepares to finally kill him, but Tiger Claw arrives to rescues him. April asks her to forget Shredder as Leo needs medical attention. Karai agrees to this and helps April take Leo back to the lair.
In "Tale of Tiger Claw", after being cursed by the Cursed Blades of Vengeance, Casey briefly flashes back to the venomous kiss Karai gave him in "The Deadly Venom" She was briefly mentioned when Leo and Mikey are on patrol.
In "Requiem", with the old lair no longer safe, Karai and Shinigami are seen taking up residence with the Mighty Mutanimals in the Bronx, but their relief at being safe is short-lived as Super Shredder lays siege to the hideout and sets it on fire. As Karai faces him, Super Shredder taunts her at how she'll die just like her mother Tang Shen. Enraged by that, Karai charges Super Shredder, but thanks to his mutation being stabilized and strengthened, Karai's tanto blade shatters upon trying to stab his mutated heart, and Karai is knocked off the catwalk and buried under debris, left to die in the inferno. Leonardo and Splinter arrive and manage to pull Miwa out, but once outside, she's not responding. Leo performs CPR on her and manages to revive her, much to Shinigami's relief and gratitude. As the NYPD and FDNY are heard approaching, Shinigami stays behind with Karai so she can be taken to the hospital by the paramedics to be treated for her injuries.
In "Owari", Karai is in the hospital, having suffered numerous bruises, cuts, abrasions, and a broken arm, but is expected to make a full recovery. When the Turtles arrive to tell her about her father's death, she too was devastated. Hoping to avenge him, Karai gives them the location of Super Shredder's hideout so they can end things once and for all. Once Super Shredder has been eliminated, Karai joins the Turtles, April, and Casey on a rooftop overlooking the city, knowing that with Shredder gone, there will be a major power struggle to fill the gap, but they will be ready for it, knowing Splinter is watching over them from the afterlife with pride.
In "The Forgotten Swordsman", Karai and Shinigami follow their Foot Soldiers to a warehouse, where they confront her over her leadership as they believe she doesn't deserve to be the leader of the Foot Clan. Karai and Shinigami easily overpower all of their soldiers, only to encounter one more adversary different from the others. That opponent is none other than Karai's old mentor Hattori Tatsu but even reverting to her snake form isn't the enough to beat him but escapes with her life thanks to Shinigami and her dark magic tricks. She and Shinigami arrive to the Turtles' lair to ask them for their help against who is after the Kuro Kabuto to gain total leadership over the Foot Clan. Mikey and Raph arrive after a battle against Fishface and the revived Rahzar and she becomes extremely shocked upon hearing the Kabuto will be used to bring Shredder back from the dead. Shinigami explains that if they keep the helmet away from Tatsu's hands, the ninjas will side with Karai, their rightfull leader. Their only chance for survival is to take him down. They create a plan to get the Kabuto. Karai, Leo, Shinigami and Mikey'll turn off the lights and fight Tatsu while the others stay alert to Foot Soldiers.
Tatsu manages to best everyone present Tatsu but Karai manages to strike Tatsu's Oni mask revealing, to Leo's shock, he's totally blind. However, even though he was born blind, he possesses an extremely good sense of hearing, leading to people believe he had a sixth sense. He proceeds to explain his backstory of how the Shredder found his skills quite useful to the Foot Clan and became the "Blind Swordsman" before the other members mocked him. He also reveals how Karai attempted to eliminate him with her newly-recruited soldiers, shocking Leo once more. Karai admits her mistake but asks Tatsu to leave her family out of this but Tatsu refuses to hear any of her words and assures her she and her friends and family will suffer the same fate.
Tatsu takes Shini and Mikey out of the battle and Karai angrily mutates but is still no match against her old mentor. He prepares to finish with her life, only to fail when Casey throws his explosive pucks at him to prevent him from killing Karai. During another battle, Leo gets an idea: he attempts to disorient Tatsu by throwing at him Casey's pucks while Karai times her steps with each explosion but he manages to block Karai's sword attack but what he didn't know was that Leo jumped behind him and disables his hearing with a nerve move he used on Rapahel earlier. Karai sees this chance to defeat her old teacher with her mutant form and succeeds. Karai changes back to her human form, informs the soldiers they're being used by Tatsu just like Shredder and the Foot Clan deserves a noble and moral destiny before asking Tatsu to return to Japan and rot there. Tiger Claw, Rahzar and Kavaxas arrive to take the legendary helmet and the demodragon drains Tatsu's soul leaving him dead before, under Tiger Claw's orders, attempting to kill the Turtles but April creates a shield with her psychic powers to protect everyone present allowing Tiger Claw, Rahzar and Kavaxas to escape with the Kuro Kabuto. Casey and Shinigami are taken to hospital and Karai apologizes for foolishly going after Tatsu by herself but the team forgives her and they all promise to stop Kavaxas once and for all as a team.
In "Heart of Evil", Karai assists the turtles to find the next phase of Tiger Claw's plan to revive Shredder. She and April are on a motorcycle chasing Bebop however he then blasts them but April saves herself and Karai from falling. Karai, with the turtles watch over Don Vizioso's hotel and is waiting for Kavaxas and Tiger Claw to show up. Karai with her mutant form pins down Kavaxas to allow April get the Seal of the Ancients. Karai with the turtles are then defeated again by Kavaxas.
In "End Times", Karai and Leatherhead are called by Michaelangelo to help them defeat Undead Shredder and Kavaxas once and for all. Although Leo had told her to rest up, Karai sarcastically jokes about this to Leonardo. She and Leo are seen attacking the Undead Shredder and Kavaxas. Because Kavaxas' ulterior schemes had gone against Tiger Claw's plans, Tiger Claw sides with the Turtles. Eventually, alongside Tiger Claw. Karai and Leonardo watch as Kavaxas is sucked back to the Netherworld along with Shredder pushing him to the portal. Afterwards, with all of Manhattan restored to it's former glory, Karai and Leo embrace their father's spirit and emotionally watch his spirit take the skies once more, knowing that Splinter is still there with them, in spirit. As the team admires a very beautiful sunset, Leo decides that it's time to return home. However, Karai wraps her arm around Leo's shoulders and politely requests him to linger around, as she is fascinated by this scenery, willing to "enjoy and appreciate this moment...for a little while longer".
In "When Worlds Collide", Part 1 and Part 2, the conclusion that Raph's brothers all have girlfriends, Karai is shown playfully sparring with her love interest and younger adoptive brother Leonardo in the Dojo part of the Turtles' lair. As they exchange some witty banter, Karai charges at Leo, but in a non-life threatening and jocular manner, stating that although she likes him, she "won't go easy on him" (a possible reference to tough love). Later in the episode after Newtralizer has blown up Mikey she can be seen cuddling Leo's shoulder in condolence.
In the 4-part episode story arc Monsters and Mutants, during the episode "The Frankenstein Experiment", Karai briefly appears while Leonardo, who is trekking to Frankenstein's castle through a haunted forest, is suffering from horrific hallucinations of the Shredder (in all his forms) by The Pharaoh. She was summoned next to Undead Shredder because Leo is facing his fear of both Shredder and him taking Karai from him again. After Leo realized it was only a hallucination, Karai (as a vampire and snake-like form with the Super Shredder behind her, which gravely worried the Turtle leader) disappeared through a puff of dust. Because of this hallucination, it's implied that Karai may have also been bitten and turned into a vampire back in New York City, and unofficially restored when Mikey fatally stabbed Dracula.
In "The Foot Walks Again!", Karai appears for the last time, having become a fully-fledged heiress to the newly reshaped Foot Clan (which is now allies with the Turtles) with her right-hand Shinigami and some of their Foot Soldiers. They are patrolling the city from the rooftops, searching for Purple Dragons, but find that the city is at peace. They are about to call it a night when they spot Bebop and Rocksteady with some weird-looking robotic Foot Soldiers from the 1987-1996 TMNT realm, attacking a secret Earth Protection Force warehouse facility in search of a transmat microchip too pen up a portal to Dimension X. She alerts Leo and the Turtles, who then play a prank on her by confusing her with the 1987 Turtles. Surprised by this, she asks the Leo and Donnie what the heck she is seeing, then insults the alternate reality Turtles from their looks, much to 1987 Raphael’s annoyance replying “Nice to meet you too. With friends like these who needs enemies?”. Once Bebop and Rocksteady exited the base, she and the Turtles ambushed them but were also ambushed by the 1987 Foot Clan and Shredder. Karai gasps as she saw Shredder supposedly alive (but isn't aware that this Shredder comes from the 1987 TMNT world), who then orders the Foot to attack them. Karai's Foot Clan then saves her and the Turtles from the 1980s Foot Soldiers. While the 1987 Shredder began laughing and gloating, Karai angrily charges and attacks him with ease, possibly thinking that he was the Shredder from this current universe. Due to Shredder's cowardliness, arrogance, the fact that he tries so hard to look menacing, he really isn't. He refuses to fight a girl, he orders the Foot to destroy her while saying she is a little too tough.
After the 1987 Foot and Bebop and Rocksteady escaped Karai and the Turtles's wrath, she questioned the 8 Turtles how will they get the chip that will open a portal to Dimension X. Karai isn't present in the final battle (The Big Blow-Out), marking this episode the last appearance of her and her Foot Clan.
"I have to admit that I’ve never seen any other version of Karai, so I really have nothing to compare her to -- which is kind of a good thing, because then I just get to play her as I see her myself. But she’s sort of feisty, kicks butt. She gets to have a little going on with Leonardo. What I like about playing this character is she’s not all bad. She has a conscience that she has to wrestle with." - Kelly Hu describing Karai
Hamato Miwa is the only child and daughter of Hamato Yoshi (Splinter) and the late Tang Shen, who was taken away from Splinter by Oroku Saki when she was just 1 year old and renamed Karai. When Splinter came to fight the Shredder after 15 years, Shredder revealed to Splinter that he kidnapped her, as shown in "Showdown, Part 2".
Karai brings a whole new level of chaos and complication for the Turtles, especially Leonardo...and Splinter. Voice actress Kelly Hu stated in an interview that she does not see herself voicing a villain, but rather "playing someone who wants certain things in life; has made certain choices, and goes after them." When asked about what she thinks makes Karai such a popular and unique character, Hu answered: "I think people love these little tough girls. She's got lots of attitude and she's [very] sarcastic at times. You just never know what she's going to do. She's always surprising you – you think she's going to turn one way and she goes the other."
When Karai makes her first appearance in "New Girl in Town", she is portrayed as quite a rebellious, intelligent, arrogant teenaged kunoichi who stirs up trouble at times. Different from the Mirage and 2003 versions of the character, which are mostly serious and stoic, the 2012 version is much more inclined to taunt, and be extremely sarcastic, even directly at Shredder. She has some nerve to talk back to the Shredder when she want to. However, she is not entirely sadistic, as she showed genuine mercy when April claimed that her mother also passed away when she was young, thus giving the girls a thing they had in common. And she spared Leonardo twice in her debut episode, going directly against Shredder's orders.
However, she’s a beautiful young girl. She has style and poise and would be able to blend in to the city streets with street clothes. She speaks fluent English and Japanese with ease and understands the cultures of many around her, including the Kraang's. She wears ninja gear which looks somewhat stylish and fashionable (as Leo was attracted to her). Karai is very good at planning and perfecting schemes, meaning that she’s well educated. This shows that she is two-faced: although she usually maintains a calm, yet arrogant and sarcastic when dueling (especially with Leonardo, in addition to exchanging some flirtatious, witty banter with him), she shows little to no problems with dueling with the other innocent Turtles, as well as going as far as heedlessly, yet deliberately unleashing dangerous damage to slay them, and would do so if necessary. Karai knows what she wants and will do absolutely anything to get it. While she takes her work seriously, she possesses a dark sense of humor, and trades verbal barbs with Leonardo as they both engage in a battle of wits, despite Leo having sentimental feelings of romantic interest to her.
However, she still does operate on a bit more complex code than the Foot Clan and Shredder himself, and, at one point, she seemed to have a bit of a greater concern over the community around them (and the Turtles) than the Shredder did. For example, she openly objects to Shredder's plan to ignore the Kraang and his reasoning that Vengeance against Splinter is all what matters and the fate of the city and all its inhabitants was of no concern. Until Karai suggests to become allies with them to use their advanced tech.
By Season 2 after Shredder revealed who Splinter is, she got more angry and she wanted revenge. By the 14th episode of that same season, she felt threatened, by the fact that Shredder came back from Japan to bring Tiger Claw with him to replace her as his second in command. It was at that moment that the biggest change in her personality took place. All of a sudden, she lost her top position, which basically meant she lost everything. All she accomplished in Shredder's absence, such as the Robot foot soldiers and Chrome Dome super Foot robots she successfully brokered with the Kraang, wasn't good enough to keep her place as his right hand woman because she did all of it without his consent.
This brings out a side of her she kept hidden for a long time, the side which always doubted the morals of what she had been doing. Because honor was everything, which is what Shredder had taught her when raising her, keeping a torn photograph of her mother to remind her what she actually was doing all of this for. She begged Shredder to spare Splinter because she wanted him to see them fight when the odds were even. Where's the honor in killing somebody who cannot defend themselves?
When in The Wrath of Tiger Claw, She and Tiger Claw raided Murakami Gennosuke's shop to lure the Turtles out, she all of a sudden dropped her tanto and stopped her attack, remarking that there was "No honor in this." After having Leonardo bring her to the lair with a ruse, she said she finally believed that Splinter was her true father, she activates a tracking device with which she could lead Tiger Claw to the lair just in case if Splinter’s truth is a trap. But when Splinter takes her to the Dojo she is initially pleasantly surprised by the beauty and serenity of the Dojo and shocked to the core when Splinter presents her with the un-torn version of the picture Shredder used to keep her under his thumb. The picture shows her mother and Splinter, revealing that he truly is her father. Remorseful, she teams up with the turtles and fights Tiger Claw, who defeats her and takes her back to Shredder, who locks her up for betraying the Foot Clan.
In the remainder of season two, it's revealed that her strong willed personality is still there, as she taunts Fishface when the latter brings her food and she flirts with Leonardo when he and Raphael break her out. But all her hatred she displayed to Splinter and the Turtles is now directed towards Shredder and the Foot Clan. The same disdain she had with Shredder unwilling to pay attention to the Kraang, she also shows to Splinter when the latter tells her that he has no interest in getting revenge on Shredder. Which makes her decide to go after Shredder alone, refusing the help of Leonardo.
After being mutated Karai became very feral and unpredictable, however she kept enough of her personality to recognize her father and the Turtles, knowing they were trustworthy, being lucid enough to save Splinter from drowning and to tell Leonardo in Serpent Hunt where he could find her and in The Pig and The Rhino clarifies to him that she wanted to say goodbye before she would lose her humanity completely.
After being captured and being turned to the Foot Clan once more thanks to a Brain Worm, Karai briefly returns to her evil ways, here again was the Conniving, scheming and evil mastermind but gaining the sadism which Shredder always displayed. In addition, Baxter Stockman's experimentation gave her full control over her mutation, making her able to transform at will.
After regaining her free will, Karai sets up a new more honorable version of the Foot Clan, bringing in Shinigami as her new lieutenant and hiring ninjas to rebuild the clan and undoing Shredder's empire. As that is going on, her relationship with Leonardo also changes. Seeing as there no longer is a motive to deceive him, the two start openly hanging out. Although she forgot to mention that she went after Hattori Tatsu when recruiting the new foot soldiers because she was afraid that the former would come to the USA and take over the Foot and replace Shredder.
After the Death of Splinter, Karai spends more time at the lair, showing that she is at peace with herself, completing the search she was engaged in for all her life. Although she still taunts and teases Leonardo during some very intense training sessions, showing him tough love.
As a human, she is shown to be slightly taller than Leo and April. Karai has amber eyes, black hair that is blonde in the back with an angled bob and long ear-tails, and a very athletic body. She wears several black earrings and red eyeliner on the top of her eyelids. Karai wears a form-fitting jumpsuit fitted with silver armor, black material worn under her armor, traditional Japanese shoes, and a purple belt with a design on it like the Shredder's.
She does have a civilian outfit as well with a punk design, consisting of worn jeans, biker boots and a leather biker jacket with metal studs. This outfit was only seen in "Karai's Vendetta".
As a mutant, she is a two-armed white and purple serpent with green eyes, snake heads instead of hands and with her armor melded into her skin.
Skills, powers and abilities
Karai is still highly trained in high leveled moves in ninjutsu and hand-to-hand combat ever since she was a girl. Her weapons are a tanto knife (which symbolizes her higher rank as a full-fledged kunoichi of the Foot clan) and several shuriken. Her natural fighting skills make her incredibly agile in battle, even equal to Leonardo's high skill level.
Unlike her 2003 series counterpart, Karai eventually gets inadvertently mutated into a semi-mindless purple-and-white snake. However, due to the retromutagen that was included in the mutagen mixture, she is able to transform back to her human form for short periods, retaining snake fangs, prehensile tongue, serpent eyes and extended serpentine arms. Her face even had scaly parts and her eyes had remained a greenish color instead of their normal brown. Her snake form grants her several abilities attributed to her type of snake; such as further increasing her hearing, speed, agility, endurance, stealth and flexibility to superhuman levels, even giving her greater eyesight and night vision. However as the violent convulsions during her transformation suggests, the transformation itself actually is a very painful affair.
In addition, Karai can infect her victims with extremely lethal poisons and highly toxic venom that is quite fatal in a matter of hours, capable of seeping through skin in seconds. They have no antidote but can be counteracted with the ancient healing arts of "the healing hands" mantras. When recaptured, Stockman Fly had used his scientific intellect to give her complete control over snake form, allowing her to appear fully human without any noticeable snake traits, and even turn full snake at will. When used in conjunction with her highly extensive ninjutsu skills, her snake abilities makes her quite a formidable opponent. Some time later, she learned how to use her snakelike abilities to heal severe injuries she has sustained (such as burns or bruises) by simply shedding her damaged skin and replacing it with brand-new skin, similar to how a snake sheds its skin. As a snake, Karai can also hypnotize her opponents with her stare.
As a human, her skills as a kunoichi are so great that she can take on Leonardo one-on-one or all four turtles at once. As seen in "Enemy of My Enemy", her primary weapon choice is a wakizashi (a short yet sharp Japanese blade).
As a mutant serpent she has incredibly fast reflexes, an amazingly strong tail that can be used for whipping, constricting and crushing, and she can spit blinding venom.
She is also shown to be able to morph between her human and mutant form. As the mutagen Shredder set up was designed to turn the victim into a mindless snake, Karai does struggle to keep her human mind in tact compared to other mutants. Donatello notes that Karai is a special type of mutant, as normal retro mutagen doesn't seem to turn her back to normal.
In "Serpent Hunt" Karai reveals to have a mouth on the back of her serpent head which she can hide for surprise attacks.
In ''The Deadly Venom'' she is seen with her mind completely restored (albeit under Shredder's control) and has better control of her morphing ability, she can also switch between human and serpent, like having a human body with snake arms. She also seems to have gained telepathic control over snakes and her venomous bite (or kiss) can cause numbness, weakness, paralysis, then black out and sometimes hallucinogens. If not treated soon, the venom can prove deadly.
In "The Fourfold Trap", she is shown to be able to revert to her completely human form with no serpentine characteristics.
As shown in "Broken Foot", Karai now also has the ability to heal damage to her skin (such as severe burns) simply by shedding it when turning into half-snake form.
"Not bad - You might actually be a challenge. (knocks Leonardo to the ground in the blink of an eye) "Guess not. My name is Karai. See you around."
"You always talk to yourself?"
"I'll listen, when you beg for your life! Let's see how well you do against someone who's better than you."
"I understand... Father."
"Stop being responsible, Leo. Stop waiting for others to give you the life that you want. Go out and take it."
-New Girl in Town
"They're fighting robots?"
" Oh you were there? I didn't notice. I did see a bunch of robots though, what's their deal?"
"I like your brother, Leo. He's almost as entertaining as you."
"(Laughs) You're adorable! Stupid but adorable."
"No. You're trapped. What happens when I do this? Well now I gotta."
"I know! That's messed up right!?"
. -The Alien Agenda
"Yeah, because if Shredder finds out you have an ice cream lamp, it is over!"
"You guys need my help. You really think you can shoot down an alien warship with garbage? My point is to take down a ship like that, you need a real weapon. What if I get you a shoulder fire missile launcher? Shredder won't know about it. He's buying a big ship full of weapons down on the docks tomorrow night. All we need to do is sneak in and help ourselves. And why would I trap you? You're the only ones who know what The Kraang are up to."
Later...(to Leo, who attempts to assassinate her "father") "You're just as short-sighted and obsessed as Shredder! You want a feud? You've got one!"
"I'm not really that good about saying thank you...That was it."
- Enemy of My Enemy
"So this April O'Neil is at the center of everything?"
"What's your name? ... My name's Harmony."
"Now you try mine... Supon nabe... Turtle soup."
"A Tessen. Beautiful, unassuming... But very powerful. In the right hands."
"What makes you so special? You're the center of an alien conspiracy, protected by mutants, and trained by a great ninja master... Why?"
"What...? You lost your mother?"
- Karai's Vendetta
"Hey there princess. Miss me?"
"You've done well. Now take the message to Splinter."
"I know! Pretty cool right?"
"NO! Father! My name is Karai! Father told me what you did to my mother. And now I'm going to return the favor. Why won't you fight? COWARD!"
"So the turtles are searching for the missing mutagen canisters. This makes the game so much easier."
"I thought they'd finish me but you wouldn't let them right father?"
"Foot bots! De-shell him!"
"I never got to know my mother because your rodent master took her away from me."
- Follow the Leader
"(to Fishface) Dad put me in charge while he's in Japan, remember? So either learn some respect or I chop off your robo-legs and drop you in the sewer. Got it?
" Rise and shine Stockman. You're working for me now, well me and the Shredder. Let's move!"
-Mikey Gets Shellacne
"Not bad, How long before it's operational?"
" 9 Hours!? I want to test it on someone now! And I've got the perfect target too. April O'Neil."
"Foot bots keep the turtle busy! This is between us girls."
"Your skills are weak April. I've had years of training'"
"Like my new little toy? Robot! Eliminate the girl!"
-Target: April O'Neil
"I have no honor, but that is about to change"
"I didn't come to fight, I came to talk"
"I believe you Leonardo, I believe that Splinter is my true father"
"Father, what have I done?"
"Tiger Claw is tracking me"
"I...I don't know"
-The Wrath of Tiger Claw
"(To Fishface) "Well, if it isn't the sushi I ordered."
(To Shredder)"I am not your ...Daughter!"
(After escaping)"This isn't over, Tiger Claw."
(First words as a mutant)" ... Father ? "
-Vengeance is Mine
(To Leonardo) "Leo.... Give Shredder a couple of hits from me."
(To Leonardo) "There's nothing to be sorry about, I just wanna thank you for finishing what no one else could."
Family and Allies
Her relationship with Leonardo was turbulent, a very similar complex love-hate relationship reminiscent; as they duel across the city streets (especially on rooftops), she tries tempting him to be more evil like her by unsuccessfully luring him to the underworld, while Leo wants her to see she's not as bad as she appears to be and vice versa. They also exchange some witty banter. The two are constantly competing and dueling against each other. Some of their duels are mischievous sparring, while others are full of confrontation. If Karai beats him, she will rub it in his face. If Leo wins, he'll either try to convince her to do the right thing, get caught into a situation because of it, or (rarely) rub it in her face, almost much as she does.
Although Karai has been historically portrayed as a villainess, both Leonardo and Karai (like previous incarnations) have teamed up in achieving several common goals and are frequently depicted as having a love-hate relationship. However, this version shows that Karai is secretly the long-lost birth daughter of Hamato Yoshi (Master Splinter) corrupted by Shredder's diabolical tyranny over the years.
Despite all of this, Leo never gave up on her. Especially when it came to the truth about Karai’s family situation. As they dueled, Leo gave Karai a few truths along the way. Karai was confused and rebellious at first, but they she gave in and investigate. Finally, Karai developed genuine affection, gratitude, loyalty and respect towards Leo after learning the truth about Splinter being her birth father. She grew closely affectionate to Leonardo, reciprocating his thoughtful empathy prior to her incidental mutation as a feral predatory purple-and-white serpent.
Leonardo is the first of the Turtles that Karai meets. While she attacks and fights with him often, she never does him any serious harm and just enjoys dueling and fencing with a worthy opponent. Leonardo, in turn, was both confused by and attracted to Karai (as shown in "New Girl In Town"). She is dangerous, but Leo believed that there was some good in her but she betrayed him. She seems to be deceitful and manipulative in "The Alien Agenda", using Leo's feelings for her against him, especially in his time of need. In "Enemy of My Enemy", she returns, seeking information about the Kraang from the turtles. This time, instead of wanting to fight the turtles, she decides to make a truce with the turtles in order to defeat the Kraang ship. She goes against the Shredder's orders because she knows they'll all die if they don't set aside their differences and take down the ship. At first, the turtles (including Leo), are very skeptical of her and decline her request for a truce, but after she leads it away from the Shellraiser, they comply. Because Leo saved her and allowed her to explain herself, Karai develops some friendship for him. However, because he and his brothers tried to attack her "father", the truce was called off and her trust in him was left now uncertain. Now she's vengeful and angry towards the turtles and is willing to do whatever it takes to take them down. It was revealed in the Season 1 finale that Karai is Splinter's lost daughter (Miwa), who was raised by the Shredder. Leo seems more aggravated with Karai as she wants to hurt him and his loved ones more often, he sternly orders her that her vendetta is with him not his family.
In "Follow The Leader", Splinter told Leo that Karai is his daughter. Near to the end of "The Manhattan Project, Part 1", Leo genuinely informs Karai that Splinter is her birth father. However, she refuses to listen and harshly rejects this. Despite Leo's repeated pleas, Karai grows increasingly infuriated, fed up with Leo's "lies", threatening to slay him. But in the end, Karai overhears the group gossiping about her while hiding behind a billboard. Despite not exactly trusting them, she really started to think and question about the Splinter and Shredder situation.
In "The Wrath of Tiger Claw", Karai is shown looking at the picture of her late mother. She has flashbacks of Leo informing the inconvenient truth. Although she is still skeptical of him, she wants to investigate. After explaining her feelings of conflicted emotions to April, Karai falsely trusts Leo by pretending to believe him about Splinter, but little does Leo know that Karai actually wants to investigate the lair before making any judgement. She is taken to the Turtles' lair, much to Raphael's dismay. As the Donnie and Leo argue with Raph, Karai secretly tracks Tiger Claw, feeling that the truth might be a trap. Her thoughts changed when she follows Splinter into the dojo, fascinated by it's beauty. Furthermore, Splinter shows his daughter photographs of himself as a man with Tang Shen, continuing to convince her (for real this time). After Karai finally (and genuinely) learns the truth by seeing it herself, she realizes the enormity of her scheme. As a result, Tiger Claw in trying to terminate the Turtles and Splinter, which caused Tiger Claw to take Karai back to Shredder (who confirms that Splinter is her true birth father) and is locked up in a jail cell.
In "Vengeance is Mine", Leo and his brothers staged a rescue operation to get Karai from Shredder. It worked well and Karai was reunited with Splinter. When Leo and Mikey were training, Mikey threw one of his water balloons at Leo, which made Karai snicker and giggle. When Karai was planning on taking down Shredder, Leo wanted come along with her. Karai came close to Leo, supposedly to kiss him but instead treacherously blinded him with a smoke egg. Splinter, Leo and his brothers went to rescue Karai again. Leo was about to rescue Karai when all of sudden Shredder broke the chain that was holding Karai's cage, which caused her to fall into the vat of mutagen. When she becomes a feral and predatory mutated purple-and-white serpent, Leo appears to be one of the only people (aside from Splinter) that can help briefly restore Karai's mind by reminding her of who she is.
In the third season, Karai is brainwashed with a brain worm by Baxter Stockman turning her evil once more but it was worse than before. It was also giving her a greater control over her mutation. It was Leonardo's use of healing tantra which released her from the brain worm.
After that Karai invited an old friend from Japan, Shinigami to help take Shredder down once and for all. Later they then invited Leo to join and all three of them started guerrilla operations to shut down the Shredder's criminal empire. It was around that time that their relationship changed, seeing as how they would argue as a couple would and that Leo wouldn't even speak up after Raphael referred to Karai as being Leo's girlfriend.
In "Owari", Leo and his brothers visited Karai at her hospital bed, informing her of Splinter's death. She gives them the location of Shredder's hideout. Furthermore, Karai holds hands with Leo. In a weak, but genuine voice, she wishes him the best. And at the end of the episode Leo and Karai were seen sitting together on a rooftop overlooking the city, enjoying their victory over Shredder and comforting each other in the aftermath of the battle. Leo once again apologized for Splinter's death, but she forgave him. Throughout the fifth and final season, Leo and Karai renew their relationship with a more romantic pairing, as shown in "When Worlds Collide, Part 1". As they mischievously spar while exchanging some flirtatious witty banter, Karai mentions that although she likes him, she won't go easy on him, similar to Raphael would do.
Raphael, Donatello and Michelangelo
Raph is the second of the Turtles that Karai meets, and Raph is the first to find out about Leo’s friendship with her. Unlike Leo, Raph immediately distrusts her. He intensely hated Karai from the moment he saw her. He tries to warn Leo that she is the enemy and not to trust her. Raph came up with the idea of setting a trap for Shredder and (like the rest of his brothers) attempted to assassinate the Shredder. He still does not trust her when she wants to help defeat the Kraang.
Donnie does not know too much about her mainly because Leo never mentioned her until after they revealed her in The Worldwide Genome Project headquarters. Based on Donnie’s observations of her, he does not like her because of her need to cause trouble. Furthermore, Donnie (having a similar approach to Raph) also immediately distrusts and hates Karai, yelling "I don't know who she is, but I HATE HER ALREADY!" He is wary of Karai's tactics and does not trust her at all, not even when she offered to help him and his brothers fight the Kraang. Donnie also was a part of the attempted assassination of the Shredder.
Mikey also doesn't know too much about Karai and was surprised that Leo trusted her. When she wanted to help fight the Kraang, Mikey was wary of her. Mikey also participated in the attempted assassination. They see her as an enemy working for the Foot, but she sees them more as play toys for her amusement. In Showdown, it is revealed that Karai is Splinter's daughter, Miwa, who the Shredder took and raised her as his own daughter after the events of their final battle. When Splinter told the turtles about this, they were all shocked and Mikey questions about Karai being their "sister". The Turtles rescued Karai from The Shredder in Vengeance is Mine. They brought her back to Master Splinter, where he was shocked to see his daughter return. Later, Karai watched the Turtles train and she giggled when Michelangelo threw a water balloon at Leonardo's face. At this point, the Turtles see Karai as a part of their family. When Karai was mutated, the Turtles and Master Splinter were deeply depressed. Mikey asked Donnie if he could make a retro mutagen for Karai but Donnie stated "I hope so".
April is the first female human that she has met in the whole series. Based on their brief encounter in "Karai's Vendetta", they seem to have quite a lot in common. They both know how to speak Japanese, they both know how to drive a motorized vehicle, they're both kunoichis (except Karai has better Martial Art skills), they are both the romantic "interests" of one of four Turtles, and both of their biological fathers have been mutated into animals. They seem to become enemies in "Karai's Vendetta" (though Karai does seem to have a regretful expression on her face not very long after she attacks April). It is also suggested that Karai dislikes April somewhat and is jealous of her, due to the fact that she is very special and important to the Kraang and Splinter (a value that Karai doesn't think she has). At the very end of this episode, however, Karai appears to show signs of empathy and feeling slightly sorry for April when the other girl mentions that she lost her mother. If they weren't on different sides, it's likely that the two could be very good friends. However, their current views of each other have change now that Karai has found out and accepted that Splinter is her biological father. Also in The Wrath of Tiger Claw, she chased down April to just talk to her instead of fighting. She then opened up to her about everything that was happening, Splinter possibly being her real father, Shredder lying to her for her whole life and where her loyalties lied, and her possibly betraying the Shredder which surprised April. They are then seen enjoying each other's company as they had a conversation until the turtles arrived. She then told the turtles that she believes Splinter is her biological father. April then tells them that she believes that Karai believes this to be true showing that she now trusts Karai.
Karai is Tang Shen's daughter, along with Master Splinter's. When she was an infant, her mother perished at the hands of Shredder when she intercepted a blow meant for Splinter, and was taken in by him. He then raised Karai as his own child and fed her countless lies about how her mother died and who committed the act. Karai has known this false truth for a big portion of her life, but when Splinter showed up in Shredder's hideout in "Showdown", her true feelings on the situation are exacerbated even more and she now desperately hopes to avenge her own mother's death by killing her true father. Even though she doesn't know what her mother was actually like, she carries a torn-off, dilapidated photo of her mother around with her. It is likely that this was part of a grander, family photo like the one Splinter has in the lair, but the Shredder probably ripped Tang Shen's part off to conceal his own lie.
Karai is none other than Splinter's biological daughter. In the episode "Showdown Part 2", Splinter discovers this after the Shredder reveals to him that he took his daughter, Miwa, away and raised her as his very own child. When Karai soon shows up, he is then able to turn Splinter's own daughter against him by using what he had formerly told her about whom killed her mother, Tang Shen. She then tries to fight Yoshi, but he manages to avoid her attacks and escapes. She then demands to know why he won't fight with her and calls him a coward. He then leaves, heartbroken at what the Shredder has done to his daughter....In "Follow The Leader", she demonstrates how truly spiteful and vengeful she has now become towards him. She hates him to the point where she wanted to kill the Turtles before his very eyes and ruin his life in so many more ways. When she successfully tranquilizes Splinter in "The Manhattan Project, Part 1", she seems to view this as a big victory and she also even appears to draw some sadistic pleasure from doing this. It is very clear that Splinter knows that his daughter is fully alive, active, and working alongside the Shredder, In "The Manhattan Project, Part 2", she over hears Splinter talking to the team about him being her biological father and whether if she will figure it out and accept it is her decision. She then has a guilty expression on her face suggesting that she's starting to question herself and everything else. In "The Wrath of Tiger Claw", her knowledge of the truth caused all her hatred of him to disappear and after her rescue in "Vengeance is Mine", she hugged him for the first time. After her mutation into a snake-like creature, her love for him gave herself the strength to fight her new instincts and not devour him. In "The Invasion, Part 2", mutant Karai saves Splinter from drowning in the sewer waters and gently tapped on his shoulder to check his vital signs, which shows that she deeply cares about her father.
Shinigami is an old friend of Karai's from Japan and has tried to help her rebuild the Foot Clan in a more honorable image.
Karai's former relationship with her kidnapper was actually quite complicated. She seems to fear The Shredder at certain times, just like Bradford and Xever do, yet she obeys him, but she doesn't appear to respect him as much. She would make remarks and argue with him. It is possible that she wants him to respect her equally, such as when she mentions The Kraang and shows him the droid she had picked up, attempting to intrigue him somehow. In "Enemy of My Enemy", just a little more insight is given into Karai's relationship with The Shredder. Karai saves him a total of two times in this very episode. She tackles him out of the way to prevent him from getting zapped by an electro-grenade and bravely jumps into the sea to save Shredder from drowning towards the end of the episode.This proves that Karai truly loved Shredder as her father despite constantly disobeying his orders. That all changed when she finds out that Saki is not her true father and had manipulated her since the very beginning, she betrays him and he has her locked away in his lair's dungeon, after that event she began to hate him for lying to her for her entire life. In "Vengeance is Mine", she learned that it was Shredder who was responsible for her mother's death and that he kidnapped her. She wanted revenge on him so much that even after her real father told her that "revenge only leads to more pain”, she rushed to his lair to face him.
Karai did seem to stand up for both Bradford and Xever in a way when she told the Shredder that his own men got turned into hideous freaks when she wanted Shredder to try and help her figure out what was going on with the Kraang. But when Shredder left for Japan and Karai stood in as head of the Foot, she took obvious delight in bossing them around; Fishface remarked that she should watch out because she wouldn't be in that position forever.
At the moment they first met, they did not like each other. All of the other members of Shredder's forces seem to be rather stunned to see such a menacing looking man beast, while Karai coldly asks why The Shredder has enlisted yet another freak. Right afterward, Tiger Claw tells the Shredder that he is quite disappointed that this is the Foot Clan he told him all about. Karai continues to show no respect by teasing him about losing his tail. She was angered by the fact that Shredder made Tiger Claw his second-in-command instead of her, but was willing to work with him until she finally accepted the fact that Splinter was her real father and betray him and the Shredder.
Bebop and Rocksteady
- The Mutation Situation (cameo)
- Follow the Leader
- Mikey Gets Shellacne
- Target: April O'Neil
- The Manhattan Project
- The Wrath of Tiger Claw
- The Legend of the Kuro Kabuto (cameo)
- Vengeance is Mine
- The Invasion
- Return to New York (2012 TV series episode) (as a picture)
- Serpent Hunt
- The Pig and The Rhino
- Casey Jones VS. The Underworld (cameo)
- The Noxious Avenger (cameo)
- Clash of the Mutanimals (cameo)
- The Deadly Venom
- Tale Of The Yokai (as Baby Miwa)
- Attack of the Mega Shredder! (cameo)
- The Fourfold Trap
- The Forgotten Swordsman
- Heart of Evil
- End Times
- When Worlds Collide, part 1
- When Worlds Collide, part 2
- The Crypt of Dracula (cameo)
- The Foot Walks Again! (final appearance)
- Miwa strongly resembles Leonardo's Wife from the Mirage TMNT miniseries Tales of Leonardo: Blind Sight. In this story, Leo experiences a vision of another life where he is a turtle samurai in feudal Japan. He has an unnamed human wife, and together they have a daughter named Yumi. Leo's wife and Miwa have facial structures and hair styles that are very similar. But unlike Miwa, Leo's wife also ties her hair, wears no eyeliner or face paint, and her widow's peak is positioned higher and away from the "villainous widow's peak" style. Overall, Miwa as Karai looks like a more evil version of this character.
- The false name that Karai gave April in "Karai's Vendetta", "Harmony", can be written in Japanese as "Miwa" (美和).
- In "The Wrath of Tiger Claw", Karai finally learns and accepts the truth of Master Splinter being her real father.
- According to Shredder, Karai wanted to have a pet.
- Karai's ability to change her current mutation, back to her "normal" self again, is an act very similar to of the snake lady from the movie The Snake Woman and the most recent Hisss.
- Karai's mutant form with the snake heads for hands bears a slight resemblance to previous Ninja Turtles' villain Scale Tail.
- Karai is 1/8 Chinese through her mother Tang Shen, who was 1/4 Chinese through her grandfather.
- The writers toyed with the idea of mutating Karai into Venus de Milo, a female mutant turtle who appeared in Ninja Turtles: The Next Mutation, but this idea was eventually scrapped-possibly because of co-creator Peter Laird's intense hatred for her-and replaced with an original mutation.