"The fourth match…" Hayate announced, "begins… now!"
The two Uzumaki reached into their pouches and dug out their last remaining kunai; hooking a finger through the hole in their kunai's pommel, Naruto and Karin each simultaneously drew and threw their weapons in one smooth motion. However, they were too evenly matched at throwing ninja tools; the kunai collided into one another in midair and clattered to the floor.
Seeing that his initial approach had failed, Naruto decided to turn to the ol' reliable:
"Shadow Clone Jutsu!"
Geysers of white smoke burst out of the ground one after the other, until Karin was surrounded by ten of Naruto's Shadow Clones, not including his original self.
"Just Clones, huh?" said Karin dismissively, eyeing the army of Naruto surrounding her.
But when she activated her Mind's Eye of the Kagura, Karin quickly discovered that she couldn't tell apart the fakes from the real deal; these weren't your garden variety Clones, but solid Shadow Clones!
Karin quickly lost track of her real opponent amidst the sea of orange jumpsuits. Like a well-choreographed dance, Naruto's Shadow Clones dipped in and out of her range, striking when her back was turned, attacking while she was distracted and tripping her up when she was preoccupied with a different Shadow Clone.
Since Naruto had divided his chakra equally into eleven parts, Karin was finding it impossible to find the real one. And simultaneously, Naruto was finding it difficult to outlast a fellow Uzumaki clan member in a contest of stamina; Karin's vitality was even greater than his own, since she wasn't dividing her chakra like he was doing, and her Uzumaki blood was purer!
"Clone Jutsu!"
Even so, getting hit repeatedly was not a pleasant experience for Karin, so to buy herself some time, she had to resort to one of the very few Jutsu that she had learned in the Hidden Grass: the regular old Clone Jutsu. Clones didn't cost as much chakra as the solid Shadow Clones, but they were illusory; meaning that they were completely harmless, and that Naruto could easily identify the fakes just by punching them.
Still, they would have to suffice while she searched for the real Naruto…
"Mind's Eye of the Kagura!"
And that's when Karin finally found the flaw hidden within the seemingly perfect Shadow Clone Jutsu. The Shadow Clones were indeed indistinguishable from the original at first, but their chakra levels would continuously drop, while the real Naruto had an Uzumaki physique just like hers, making his lost chakra continue rapidly regenerating.
She had found the path to victory!
Karin began her counterattack with renewed vigour; she stopped caring about getting struck by Naruto's Shadow Clones' fists and made a beeline for the real one. Naruto had made one of his Shadow Clones hang slightly behind the others, making it seem as though it were the original, staying out of the melee to avoid getting hurt… but unfortunately for him, Karin had seen right through his ploy!
"Found you!"
Karin jumped into the mass of flailing Shadow Clones and landed a solid punch in Naruto's jaw, sending him sprawling to the floor. The shock immediately caused his remaining Shadow Clones to dissipate into smoke, but when she darted over to kick him while he was down, another explosion of white smoke forced her to retreat.
"Shadow Clone Jutsu + Transformation Jutsu!"
It was one Naruto's and Sakura's favourite combos; using the smoke from the Shadow Clones to hide the Transformation Jutsu's hand seals. When the smoke cleared, Karin and her army of illusory Clones found themselves facing an army of Naruto Shadow Clones; except this time, they were disguised as her!
"Are you an idiot?" Karin taunted him. "I can easily tell which ones are mine!"
The Clone Jutsu generated illusions, instead of actual, real, solid-and-thinking Clones. As such, Karin needed to dedicate a part of her mind to consciously control her Clones' actions, so as a result, she could easily tell which ones were hers and which ones were Naruto's.
In most cases, the Clone Jutsu would be used to create illusory copies that perfectly mirrored your actions, to confound the enemy while attacking or defending (and to save on brainpower), but as long as you were good at parallel thinking and multitasking, you could make the illusions do anything you could imagine, and not just mirror your moves.
However, Naruto either didn't know, or had simply forgotten about this feature of the Clone Jutsu. Technically, to pass the Hidden Leaf's academy exam to graduate to Genin, one needed to have mastered the Clone Jutsu. Naruto had failed to graduate three times because of this Jutsu's brainpower and chakra control requirements, but he had managed to pass the academy exam by using a variant.
As such, Naruto was much more used to the "superior" Shadow Clones, which operated independently from him. Indeed, once they were made, Shadow Clones would be nearly completely separate from their caster. So, whenever there was a change of plans, Naruto would have to call out his new instructions to his Shadow Clones!
And that was a flaw that Karin had just happened to uncover during her brief melee with the Shadow Clones a few seconds earlier…
"Transformation Jutsu!"
Suddenly, Karin and her regular Clones all turned into Naruto!
Karin knew which Naruto was the real one, Karin's Clones didn't really matter since they didn't exist in the physical world, and Naruto knew he was real… But Naruto's Shadow Clones didn't know which one of them was the real one; they usually operated on the basis that the one calling out the orders was the original!
"Get him!" Karin cried out, pointing at Naruto. "He's the fake!"
"Don't listen to him!" Naruto growled. "I'm the one and only Uzumaki Naruto! Ow! Stop that, you morons!"
Naruto was forced to dispel his Shadow Clones, leaving him in the undesirable position of having no backup while a girl was sitting on his chest, punching him in the nose repeatedly! Still, Naruto was much better trained and physically stronger than she was, so after enduring a few more hits, he managed to reverse their positions, mounting her instead and pinning her shoulders against the ground.
"Give up!" Naruto told her. "I don't want to have to hit you (more than I already have)!"
Karin opened her mouth, but instead of answering him, she bit him in the inner thigh… uncomfortably close to where Naruto kept his family treasure. She fully expected to receive the healing boost that others would obtain when others bit her, but instead of being healed to full, she only received a mouthful of hot, salty blood. Unfortunately for her, Naruto's healing factor didn't come from his Uzumaki blood, but from the Nine-Tails…
"Ow!" Naruto yelped in pain. "What's wrong with you? Are you a kid, or something!?"
He began raining fists down on her face to force her to let go; her glasses shattered into pieces, but she screwed her eyes shut to avoid getting blinded. Karin hung on for dear life, even though her face was getting all bloodied up, and Naruto's fists were full of glass shards.
"Karin, just admit defeat!" Sakura cried out to her. "This isn't worth getting your face kicked in! You don't have anything to prove to anyone but yourself, so please, just let go…!"
"Naruto-kun…!" Sakura heard Hinata softly call out in concern.
Finally, Gekko Hayate stepped in to separate the combatants.
"It looks like she fainted a while ago," he observed. "Well, that makes Uzumaki Naruto the victor of the fourth match… nice going, kid."
Despite having won, Naruto didn't feel that great about his victory, due to the way in which their match had ended. He had wanted to ask his fellow clan member about herself, but she had been too preoccupied with winning to engage in small talk.
Still, Naruto was guessing that there was something Karin wanted out of this exam; something so precious to her that she would stake her life on it; that was something he could respect. After all, how could he blame someone for wanting to follow their dreams? He was the biggest dreamer of them all!