Kakashi had been in a lot of bad weather.
Snow that froze the breath in his mask. Desert wind that scraped the skin off your bones. The thick, metallic stillness in the air right before a lightning storm.
The fog on the lake in Wave Country was… different.
It wasn't just sight it took. It swallowed sound, muffled chakra, turned everything soft and close and wrong. The little boat cut through it with barely a ripple, and the world shrank to wet wood underfoot, the faint splash of oars, and four heartbeats that were much too young for this kind of mission.
Five, counting the bridge builder.
Naruto sat on the prow, one foot up on the edge like he was starring in his own heroic painting. He had no business looking that proud on a glorified fishing skiff.
"I'm telling you," Naruto said for the third time, voice too loud in the mist, "this is finally a real mission. Demon Brothers, boom, taken out." He punched the air. "Next time some bandits show up, I'll blow them away in one shot!"
Kakashi let his eye slide half-closed. "You mean after you check that they are, in fact, bandits and not, say, a village elder in an unfortunate coat."
Naruto spluttered. "I know what bandits look like!"
"Mm." Kakashi turned a page in his book. "Do you?"
Behind Naruto, Sasuke stood with his hands in his pockets and his weight balanced just-so, like he was always waiting for the next attack. The fog beaded on his dark hair and lashes. He hadn't said much since the Demon Brothers—just brooded, analyzed, and occasionally shot Naruto a look that could cut through stone.
Sylvie sat closer to the center of the boat, one hand curled around the gunwale, the other resting on her knee. Her glasses were dotted with mist; she kept pushing them up with a paint-stained finger. A scroll case bumped against her hip with the rhythm of the oars.
She wasn't talking either, which meant she was thinking. Or worrying. With Sylvie, the line was thin.
Tazuna hunched at the back, clutching his bottle like a life preserver. His breath smelled like stale alcohol and old fear.
"Hey, old man," Naruto said, twisting around. "What's Wave like? Is there, uh… ramen?"
Tazuna snorted. "You'll be lucky if there's anything left that Gato hasn't taxed into the ground."
Naruto frowned. "Who eats money?"
Kakashi turned another page and decided not to engage with that.
The mist thickened as they reached the center of the lake. It crawled along Kakashi's skin, heavy and damp. His ninken hated this kind of weather—scents warped, sounds bounced. The perfect place to vanish. Or to kill someone who couldn't see you coming.
He let his senses stretch anyway. Footing. Water depth. The kids' chakra, bright and clumsy and human in the muffled gray.
Sylvie shifted suddenly. Kakashi caught the flicker at the edge of his vision: her shoulders tensing, the way her hand tightened on the wood. Her head turned, just slightly, toward the blank wall of fog on their left.
Naruto noticed nothing. Sasuke noticed Sylvie.
"What," Sasuke said quietly.
Sylvie's eyes were narrow behind her glasses. "Something… feels wrong," she murmured. "Like the air is holding its breath."
Kakashi agreed. He'd felt it a minute ago. But he'd learned a long time ago to let his students notice what they could before he stepped in. It told him useful things.
He heard it then—not with his ears, but with every instinct that had kept him alive past the age of twelve.
Killing intent.
It rolled over the boat like a cold wave, thick and suffocating. Naruto froze mid-gesture, mouth still open. Sasuke's hand flew to a kunai. Sylvie's grip slipped on the gunwale; for an instant, Kakashi thought she might actually throw up.
Tazuna went white.
"Down," Kakashi snapped.
He didn't raise his voice. He didn't need to. Fear did the work for him. The three genin ducked on reflex, more out of instinct than obedience. Kakashi was already moving.
The sword came first.
It split the fog with a whistle, a massive cleaver spinning end-over-end through the air. Naruto yelped and flung himself flat. The blade slammed into a thick tree trunk on the shoreline with a meaty thunk, burying itself deep enough to make the wood shudder.
The fog thinned just enough for them to see the man standing on the lake.
He was tall, broad-shouldered, wrapped in bandages from nose to chin. The bandaged bundle on his back had clearly been the sword's former resting place. Now he stood on the water as if it were solid ground, arms folded, looking down at them like they were an interesting kind of insect.
Zabuza Momochi. Demon of the Hidden Mist.
Kakashi didn't swear out loud. He did allow himself a moment of internal, resigned profanity.
"Which one of you," Zabuza said, voice rough and amused, "is the bridge builder?"
Naruto pushed himself up, bristling. "Who the hell are you?!" he yelled.
Kakashi's hand shot out, grabbing Naruto by the collar before he could launch himself off the boat and into an unmarked grave.
"Stay back," Kakashi said, voice calm. "All of you."
He stepped forward, putting himself between Zabuza and the kids.
The fog parted around Zabuza like it was afraid to touch him.
"I see," Zabuza said, eyes sliding over Kakashi's vest, his hitai-ate, his posture. "Konoha's Copy Ninja, Hatake Kakashi."
He said it like it was mildly interesting trivia. Kakashi felt Naruto twitch behind him.
"Whoa, he knows your name," Naruto whispered, too loud. "That means you're famous, right? That's so cool!"
"Cool later," Kakashi muttered. "Terrifying now."
Zabuza's gaze lingered on his covered eye. "They sent to babysit a drunk and three brats?" he drawled. "The Leaf must be desperate."
"Sorry," Kakashi said cheerfully. "We were out of babysitters, so you got me instead."
He closed his book with one hand and slipped it back into his pouch.
"Naruto, Sasuke, Sylvie," he said, tone dropping into the flat register that meant business. "Formation C. Protect Tazuna. Do not engage if you can help it. You are not ready for this opponent."
Naruto made a strangled noise. "But—"
"Do not engage," Kakashi repeated, and let a sliver of killing intent seep into his own voice.
Naruto swallowed hard. "Y-yeah," he muttered. "Fine."
Sasuke didn't argue, but the angle of his jaw said he wanted to.
Sylvie said nothing. Her eyes were on Zabuza, wide behind her glasses. Kakashi could see the sheen of sweat at her hairline.
He stepped off the boat, chakra flowing to his feet. The lake's surface accepted him with only a faint ripple.
"Momochi Zabuza," he said. "Missing-nin of Kirigakure. Aoi-level threat in the Bingo Book."
Zabuza's bandaged mouth tugged into something like a grin. "Flattered."
"Kids like yours," Kakashi went on, "should be back at the Academy, learning not to scream when someone throws chalk at them."
He tilted his head, letting the hitai-ate slip just enough to expose the faint outline of the eye beneath.
"But you got unlucky," he said. "You ran into us instead."
He lifted his hand to his forehead.
"Kakashi-sensei?" Naruto said, breathless. "Are you—"
"Don't worry," Kakashi said lightly, thumb hooking under the edge of the headband. "You're about to see something interesting."
He slid the cloth up.
His left eye opened, red and black and spiraled. The Sharingan drank in the fog, the lines of Zabuza's stance, the tension in the man's fingers. The world sharpened, colors snapping into painful clarity.
Zabuza's grin widened. "So it's true," he said. "The Sharingan."
Naruto's chakra spiked, a mix of awe and "what does that do" and "can I have one."
"Eyes up, Naruto," Kakashi said. "If you look away, you'll miss the parts where you don't die."
The fog thickened again as Zabuza moved.
One moment he was there; the next, water exploded around him as he vanished. Killing intent slammed into Kakashi like a physical blow, trying to freeze muscles, dull reaction time. It was an old trick. Kakashi had felt worse from people with less impressive nicknames.
He moved.
Steel met steel in the mist. Zabuza's sword hummed as it carved through air and water and the trunk of another tree. Kakashi's kunai slid along the edge, deflecting, turning. The Sharingan caught every twitch, every micro-shift in weight, every ripple that telegraphed the next strike.
He saw Zabuza's hand signs before they finished forming.
"Water Style: Water Clone Jutsu!"
"Water Style: Water Clone Jutsu," Kakashi echoed under his breath, mimicking the seals even as he dodged.
Water surged up from the lake, taking shape—three, four Zabuzas, each as solid as the original at a glance. They fanned out, boots slapping against the water's surface.
Behind him, Kakashi heard Naruto swear, Sasuke's breath catch, Sylvie's heartbeat stutter.
"Remember," Kakashi called, never taking his eye off the enemy, "the real body has to be near the clones. Don't let them herd you away from me."
"Like I'm just gonna stand here and watch," Naruto yelled, because of course he did.
He lunged forward—
—and Sylvie's hand shot out, grabbing the back of his jacket.
"Wait," she hissed. "Kakashi-sensei said—"
"Let go!" Naruto snapped, twisting. "We're a team! We can help!"
"Helping doesn't mean feeding yourself to the blender, idiot," Sylvie snapped back. "Look at the water. Look at the way they're moving—"
"Both of you," Kakashi said, as calmly as he could while parrying a sword slash that could bisect a tree. "Shut up and protect the client."
Sasuke moved without being told, slipping between Tazuna and the nearest clone, kunai already in hand. His chakra tightened, focused.
The closest water clone smirked and surged toward him.
Kakashi met the original's next blow, Sharingan spinning. For a moment, water, steel, and mist all blurred together. He saw the path of the sword, the angle of Zabuza's shoulder, the exact spot on the lake that would support his weight—
He stepped the wrong way on purpose.
The sword slammed into him, biting deep—
—and Kakashi burst into water, splashing back into the lake.
A substitution, freeing him to appear at Zabuza's blind spot. Kunai flashed toward exposed flesh—
The Zabuza he'd targeted broke apart too.
They traded places, clones and originals dancing in circles. The Sharingan mirrored every hand sign. Water surged and slammed and spun; the lake became a battlefield of liquid and reflection.
On the shoreline, the kids were having their own battle.
Two water clones peeled off toward the boat, grinning with identical malice. One went for Naruto, the other for Tazuna.
Naruto braced, kunai shaking a little in his hand. "Come on!" he shouted. "I'm not scared of you!"
He was absolutely scared. His chakra screamed it. But he stepped forward anyway.
Sylvie moved first.
She darted in close to Naruto, fingers already smudged with ink. In one quick motion, she dragged two short lines and a spiral on the back of his wrist. The pattern flared faintly, then sank into his skin.
"Don't freak out," she said, breathless. "And don't wipe that off."
"Huh? What are you—"
She was already turning, snagging Sasuke's sleeve as he passed and marking his forearm with the same pattern before he could yank away.
"Tch." Sasuke glared at her. "Do you mind?"
"You're welcome," Sylvie said, and shoved him toward the incoming clone. "Now go be dramatic somewhere useful."
Kakashi caught all of that in peripheral flashes. Even through the chaos, he recognized the structure of the seal—simple, elegant, anchored to their chakra.
Fuinjutsu at genin level. Interesting.
One of the clones reached Tazuna, sword arcing down.
Sylvie's hand dipped into her pouch. A paper tag snapped between her fingers, the ink on it a messy spiral with three ragged lines through it.
"Smoke!" she shouted, and slapped it onto the ground between Tazuna and the clone.
The tag sparked. A burst of thick, dark smoke billowed up, swallowing the clone's strike. The blade passed through empty air as Tazuna yelped and stumbled back, coughing.
The smoke wasn't as dense as a proper ninja tool—it had holes, thin spots—but it was enough. Enough to make the clone hesitate. Enough for Naruto, heart pounding and eyes wide, to dart in and slam his kunai into the clone's middle.
Water exploded outward, drenching him.
Naruto spat and shook his head, blinking drops from his lashes. "Ha! See that?! I got him!"
"One," Sasuke said dryly, driving his kunai into the neck of the second clone as it lunged for Tazuna. It dissolved in a rush of water at his feet.
"Yeah? And I got mine first!" Naruto snapped.
"Congratulations," Sylvie said, dragging Tazuna further back onto the shoreline, her fingers tight on his sleeve. Her face was pale; her voice was steady. "You both win the 'didn't die immediately' award."
"You kids," Tazuna wheezed. "Are insane."
Kakashi would've agreed, but he was a little busy.
The real Zabuza had apparently decided he'd had enough foreplay.
"Enough games," Zabuza snarled, forming a new string of seals. "Water Style: Water Prison Jutsu!"
The lake rose around Kakashi in a sudden, roiling sphere, slamming around his midsection like a cold fist. He felt the chakra lock in, heavy and binding. The world muffled; sound distorted. The water held him, unyielding, from shoulders to knees.
Outside the sphere, Zabuza stood with one arm submerged in the water, hand clenched. As long as he maintained contact, the prison would hold.
Kakashi tested it once, pushing chakra against the barrier. It didn't budge.
He exhaled slowly through his mask.
"Ah," he said, voice echoing oddly in the liquid. "This is inconvenient."
On the shore, Naruto yelled. "Kakashi-sensei!"
Zabuza's clone oozed up onto the bank, sword resting on its shoulder, grin shark-bright.
"Don't move," the real Zabuza called, eyes on the kids. "If any of you try anything heroic, I'll slice your sensei into pieces before you can blink."
Kakashi could see them through the curved wall of water: Naruto, shaking but furious; Sasuke, jaw clenched, eyes calculating; Sylvie, dragging Tazuna behind her like a human sandbag, fingers twitching toward her pouch.
Her eyes flicked to him. Behind the reflection and distortion, he saw the quick flare of panic in them.
She was smart enough to know exactly how bad this was.
He held her gaze as much as he could through the shifting surface and gave the slightest shake of his head.
Don't rush. Don't die stupidly. Think.
Naruto took a step forward anyway. "Let him go!" he shouted. "You big eyebrow freak!"
Zabuza's clone chuckled, rolling its shoulders. "Look at you," it said. "Barely off the Academy swingset and already mouthing off."
The sword lifted.
"Run," Tazuna whispered, voice thin. "Just—just leave me. This is my fault."
Naruto's chakra flared like an explosion.
"No way!" he barked. "We're not running!"
Kakashi watched them, heart steady despite the cold constriction around him. The plan forming in his head was risky even by his standards. It would depend on timing, on their instincts, on whether they listened to the heartbeat of the fight instead of just the fear.
His students were idiots. But they were his idiots.
And if there was one thing Kakashi knew how to do, it was improvise around idiots.
The water pressed in, cold and unforgiving. Zabuza's grip tightened.
"Let's see," Zabuza said, voice carrying eerily clear through the mist. "How long your little team lasts without their scarecrow."
Naruto's hands balled into fists. Sasuke's eyes narrowed. Sylvie's fingers brushed the edge of a scroll, lips pressing into a thin line.
Kakashi breathed in the damp, heavy air of the Water Prison, Sharingan spinning slowly in its socket.
"Show me," he thought, as the clone stepped toward his students with that enormous blade.
"Show me what you've got."