Obito staggered, black smoke curling from the edges of his face mask.
Still scarcely believing her strategy had worked, Sakura darted forwards, drawing back her gloved fist for a powerful, Chakra Enhanced Strength punch. She couldn't afford to waste this golden opportunity to land a clean hit while her opponent was still seized by spasms!
"SHA!" screamed Sakura.
Time seemed to slow to a crawl as her fist closed in on Obito's face.
Sakura felt her knuckles strike something solid— but in the infinitesimal lag between contact and the release of her pinpoint chakra blast, Obito snapped out of his paralysis and turned intangible. Despite avoiding the worst of Sakura's attack, his head still snapped back from the impact, a long crack spidering across his mask.
Unable to stop her momentum, Sakura phased through his body and crashed face-first into one of the many large crystals jutting from the ground throughout the clearing, locking eyes with the terrified man sealed inside it.
"Behind you, Sakura!" squeaked mini-Katsuyu, squeezing Sakura's shoulder to alert her.
Obito stumbled back a few paces and whirled to face Sakura, who was just turning to face him, her arms raised in the defensive stance of the basic Taijutsu style taught at the ninja academy.
…
Deep down, Sakura knew she was merely posturing.
Her Taijutsu skill was abysmally low compared to Sasuke— at least when it came to pure technique. She hadn't inherited the original Sakura's memories, only her body; so, all this time, she'd been relying solely on her incredible reflexes and the original's muscle memory in close-quarters combat.
And so far, lacking technique hadn't mattered, because she mostly relied on Ninjutsu and Genjutsu, and Chakra Enhanced Strength essentially turned her into a One-Punch Woman whenever she needed Taijutsu.
But she couldn't rely on any of that to beat Obito.
When it came to landing a blow with Chakra Enhanced Strength, timing was everything. The gathered chakra had to be released in a split-second burst at the moment of contact, making it difficult to pull off against a moving, evasive target, since you could never be quite 100% certain if or when your attack would connect (which is why original Sakura mostly used that attack to crack the ground and destroy the enemy's footing). Add to that the added complexity of timing her strikes alongside Obito's intangibility, and landing a full-power attack became impossible.
And yet, Sakura had no choice but to compete in Taijutsu.
She had just enough chakra left to maintain her superhuman reflexes, eyesight, strength, speed, and agility— without which, she'd be no stronger than your average female Olympic athlete. At best, she might manage a single Chidori, but beyond that, she would come perilously close to completely exhausting her stamina if she pushed to extract any more chakra from her cells.
…
Wordlessly, Obito and Sakura launched themselves at each other.
Sakura's first chain of kicks and punches caught Obito off guard. As a fellow graduate of the ninja academy, he'd been knocked flat by Academy Style Taijutsu more than a few times in his youth—so the opening moves, launched from that familiar defensive stance, were etched into his memory… but his opponent's wild, unrestrained strikes were unlike any systematic Taijutsu forms he had ever seen.
That being said, Sakura's attacks were nothing his eyes couldn't deal with. Seeing her outline in the pale moonlight was more than enough.
"Sha!" shouted Sakura.
She unleashed a flurry of punches, which Obito calmly caught and blocked with his palms. Quick as a flash, her hands snaked around his arms to his shoulders, gripping them firmly as she yanked his head down towards her knee… which he also blocked. Katsuyu on her shoulder opened her little mouth to spit acid at his face, but the jet of liquid flew right through his head harmlessly.
Feeling Obito resolidify, Sakura stepped in, hooked her leg behind his, and pushed, aiming to flip him onto his back. But he simply flowed with the movement and kicked her in the chest while upside-down in midair, forcing her to release him as she stumbled back.
Pain blossomed across her chest… and then the back of her head, as it struck one of the large crystals scattered across the battlefield.
"Ouch, my boobs!" Sakura gasped, her head spinning. "Who hits a girl in the chest!?"
Sakura blinked, and her eyes returned to their natural emerald colour.
If she wanted to keep her last Chidori as an ace up her sleeve, she could no longer afford to sustain her Sharingan. Not that those eyes were much better than their regular forms in the pitch darkness, anyway. The sun had slipped below the horizon more than half an hour ago.
Ox.
Rabbit.
Monkey.
Sakura's vision blurred as she felt her strength leave her, converted into chakra. Her right hand lit up with lightning, chirping with the cries of a thousand birds. The flickering blue glow illuminated her face in fleeting flashes, light and shadow dancing across her features and sporadically revealing her exhausted yet resolute expression.
"That was a waste of chakra," Obito said calmly as moved closer, wary of any more tricks like the disappearing lightning bolt from earlier. He was ready to turn intangible. "You'll never hit me with that Jutsu in your condition."
Since Sakura had plugged her ears with beeswax, she couldn't hear what he was saying. Nor could she read his lips, having turned off her Sharingan.
"Chidori!"
Sakura suddenly slammed her palm against the crystal at her back, and the Chidori's chirping of a thousand birds instantly swelled to that of an unbearably loud hundred thousand, and then to an ear-shattering million!
Obito clapped his hands over his ears and manually phased his head into the Kamui dimension, but the damage was already done. His eardrums had already burst, sending warm blood streaming down his neck from his ear canals. He could no longer hear anything but buzzing in his ears!
In short, Obito's Mangekyō Sharingan ability allowed him to automatically send whichever part of himself came into contact with an enemy's attack into the Kamui dimension to avoid taking damage… but Sakura's sound-based attack had been too fast and too indiscriminate for his ability to kick in instinctively.
BANG!
Unable to withstand the voltage emanating from Sakura's palm any longer, the crystal and the man sealed inside shattered in a shower of shards and blood, and the piercing cries of a million birds suddenly fell silent.
It was a pity that Obito's eardrums had burst— otherwise, Sakura might have seized the chance to adapt the Bell Sound Clone Genjutsu, using the amplified sound of the Chidori rather than that of a bell. Now that was an idea for another time… if she ever managed to get her hands on Guren's boobs.
"Crystal Style is pretty amazing, don't you think?" said Sakura breathlessly. "Guren really ought to open a book or two, her talent's wasted on her…!"
…
Without delving too far into the tedious details, a crystal's remarkably neat and ordered atomic structure allows it to showcase some rather extraordinary feats. And since these particular crystals were formed using chakra… well, their special abilities were naturally amplified to an absurd degree!
The first ability Sakura exploited was the piezoelectric effect:
When she physically struck the crystal with her shuriken, the mechanical deformation it underwent caused it to generate electricity. And by reversing the polarity of her initial Chidori, she coaxed the resulting negative charge into leaping through the air towards her now positively charged shuriken— thereby electrocuting Obito, who happened to be standing directly between her and the crystal!
The second ability Sakura exploited was the inverse piezoelectric effect:
By doing the opposite— directly applying an electric field to the crystal by striking it directly with her second Chidori— the crystal started expanding and contracting rapidly, thus producing sound waves from its vibrations!
The scientific principle was much like that of an ordinary speaker, only with a crystal in place of the electromagnetic coil and the permanent magnet:
Increase the amplitude of the applied current, and the crystal's song grows louder, because the Chidori's naturally alternating electrical frequency, conveniently enough, already falls well within the human audible range as the sound of chirping birds!
…
"Enough playing around!" snarled Obito as he lunged at her.
Sakura suddenly stamped on a chunk of crystal beneath her sandal, shattering it into dust. A blinding flash as bright as a flash bomb erupted from under her foot, searing Obito's eyes, which had grown accustomed to the darkness!
…
And the third and final magic trick Sakura pulled off with Guren's discarded crystals was triboluminescence: by crushing the chakra-rich crystal chunk, she disrupted its atomic structure, triggering an imbalance of charges, leading to a build-up of static electricity… which arced through the air, exciting nearby molecules and generating plasma.
Thus making… visible light!
…
Once again caught by surprise, Obito was temporarily blinded. And with his Mangekyō Sharingan disrupted, he lost his ability to phase, if only for a moment, and with his eardrums burst, he could no longer hear Sakura's footsteps!
"SHANNAROOO!" Sakura screamed.
Drawing on the last dregs of her stamina, Sakura closed her fist and took a wide, haymaker swing at the masked man, striking him in the gut with everything she had left. Obito went hurtling through the air, crashing through several diamond-hard crystals before landing limply on the forest floor— while Sakura, carried forwards by her momentum, tumbled and collapsed in a heap.
Sakura's vision darkened.
As the satisfaction of landing the punch washed over her, Sakura's eyes rolled back in her head, and completely exhausted, she blacked out.