Disclaimer: I own nothing from Katekyo Hitman Reborn.

-Updates for all my fics are erratic. I could post new chapters once a day for a while and then not update for a while, depending on how busy I am.

-Ignores Inheritance Ceremony Arc and the Curse of the Rainbow Arc. Obviously AU.

-Will focus on ten-year-later Tsuna in the past.

-No actual idea as to where I'm going with this but it's a plot and I thought I'd see what the Vongola would do when faced with the Vindice as the main enemy.

Full Summary: The Ten-Year Bazooka lands on fifteen-year-old Tsuna a year after everyone returns from the future. Fortunately, his future self isn't dead this time around. Unfortunately, five minutes tick by and twenty-five-year-old Tsuna is still walking through Namimori ten years in the past. Well, at least the only danger his younger self will face is death by paperwork, which is more than he can say when the Vindice, led by Bermuda, abandon their prison and come for the Arcobaleno in an attempt to break the curse once and for all.

Chapter 1 – Threat

As the pink smoke cleared, Tsuna could only hope his younger self wouldn't collapse under the amount of work Reborn had forced on him today, even if it was only for five minutes. His gaze landed on a wailing Lambo a few feet away and his eyes softened.

"Come on, Lambo," Tsuna stooped down and pressed a handkerchief to the boy's scraped knee. "It isn't too bad. Let's get you home and put a bandage on it, okay?"

Lambo peered up at him, his cries dying down to sniffles as he caught sight of Tsuna. "Baka-Tsuna-nii?"

Tsuna raised an eyebrow in amusement. "Still calling me that, are you?"

Lambo crossed his arms defiantly. "You were walking too fast and made me trip!"

"So you pulled out the Bazooka in revenge," Tsuna said dryly, his eyes trailing to the school bag beside Lambo and noting the way the Bovino was no longer talking in third person. "You've started school. This should be around the time I've begun telling you not to pull out your weapons whenever you want, isn't it?"

"Nobody else was around and I was mad!" Lambo protested sulkily and then added with a scowl, "The other kids made fun of my hair today and I didn't kill them."

Tsuna had to force himself not to slap his own forehead. Really, kids shouldn't go around announcing things like that so freely.

"That's good, Lambo," Tsuna sighed, running his fingers through Lambo's curls. It was no longer a full afro but it would still be some time before they smoothed out into the teenaged Lambo's hairstyle. "But you're not supposed to try to kill other people all the time anyway."

"It's your fault!" Lambo accused with a teary glare. "You said I still had to go to school even though I-Pin got the day off! It's not fair!"

Tsuna blinked, wondering why I-Pin wouldn't have to go to school. The problem with the Ten-Year Bazooka was that not everything was exactly the same in the two times. "Why doesn't I-Pin have to go to school?"

Lambo's scowl deepened. "Her Master came to town but he isn't staying long so you excused her from school when she asked! And that stupid Reborn agreed too."

Tsuna had a feeling that the decision didn't have much to do with him at all if Reborn was involved but he refrained from saying so out loud. Instead, he mopped up the last of the blood trickling from the gash, grabbed the Bazooka and handed it back to his surrogate brother, before turning around and crouching in front of Lambo again.

"Come on then, up you get," Tsuna offered, mouth twitching when Lambo huffed but hastily clambered onto his back, obviously not wanting to waste the opportunity. "You know I-Pin misses Fon a lot when he isn't around. And really, your hair is fine. Who cares what other people say? I think you look perfect the way you are."

He heard another quiet sniffle before a chin hooked over his shoulder and the arms around him tightened. With a smile, Tsuna grabbed the school bag and got to his feet, heading in the direction of his mother's house. Well, still his house too at the moment.

Absently, he checked his watch and frowned when he noted that five minutes were up. Was the Bazooka malfunctioning again? Well, it wasn't that surprising, he supposed. Just a few weeks ago, the bazooka had switched Lambo for three hours before the effect wore off.

"So who else is here?" Tsuna asked in an attempt to distract Lambo as well as to get an idea of the current time. "What's going on right now?"

He felt Lambo shrug as the Bovino replied. "Not much. Mamma left on a cruise with the idiot though."

Tsuna sweatdropped. It looked like he had passed on some bad habits regarding his father to Lambo.

"That's right; it's their anniversary, isn't it?" Tsuna remembered forcing his father to spend more time with his mom. Even the Nono had agreed.

"What's Fon doing in town then?" Tsuna asked next. "Is he just visiting?"

Lambo nodded. "And the crazy people are here too."

In Tsuna's opinion, everyone connected to the Vongola was crazy, himself included for putting up with all of them, but the only group of people his time's Lambo ever specifically called insane were-

"The Varia's here?" Tsuna said in disbelief. "For the love of god, why? Kyouya's going to flip."

"Dunno," Lambo replied dully. "Reborn said it's bonding training for everyone but all they've done so far is wake me up this morning when they got here."

"They're staying at Kaa-san's house?" Tsuna cringed as he remembered all the damage the Varia usually caused whenever they were visiting the Vongola mansion. Hell, he had set aside an entire budget for them and his own Guardians after the fifth time one of their brawls destroyed a part of the mansion.

"Of course not, Tsuna-nii," Lambo said in a superior tone of voice. "They just stopped by 'cause our house was between the airport and the hotel they're staying at. And 'cause Aho-dera got into a fight with them when he saw them."

That sounded more plausible and Tsuna was relieved that he wasn't going to find a crater in place of the house when they got there.

A chill ran down his spine and he stopped dead in his tracks as his Hyper Intuition spiked and screamed a warning. There was no immediate danger but...

"Hang on, Lambo," Tsuna instructed, breaking into a flat-out run.

"Gupyaa!" Lambo's fingers tightened in his suit as Tsuna took off for his mother's house. "Tsuna-nii! Why are you running?"

"Something feels wrong," Tsuna said curtly as he rounded a corner at full speed, the cold feeling worsening as he got closer to his destination.

His Hyper Intuition had only ever reacted like this once before, when the Vindice had tried to return Mukuro to his water prison on the grounds that Byakuran's actions had been undone so any deals made at the time were null and void. They had no proof that someone had managed to trick them into releasing the wrong prisoner so it was the only reason they could insist on and Tsuna had bulldozed them down without mercy. His last Guardian had finally been freed and he hadn't been about to let the man anywhere near Vendicare again. The Vindice had reluctantly retreated when Tsuna had compromised and had handed over a few of the more despicable Millefiore members. He hadn't liked giving even an inch but had he drawn the confrontation out, Flan would no doubt have been dragged into the discussion.

And in the end, a win was a win; doubly so when Mukuro had whispered a thank-you the moment everybody else had been looking the other way.

But what were the Vindice doing in Namimori? And, by the looks of it, at his house?

{1}

"Aren't they back yet? That stupid cow better not have done something to trouble Jyuudaime! I should've gone with him!"

"Haha, I'm sure they're just fine! Maybe they stopped to get ice-cream or something."

"Voooiii! Who cares what they're doing?! Why the hell are we even here? We already stopped by this morning!"

"Ushishishi. Nono did tell Boss that we're supposed to interact with the Prince's servants."

"Who the hell are you calling servants, you damn knife freak! Get the hell out of Jyuudaime's kitchen!"

From his perch on the back of the sofa, Reborn released a short sigh as he surveyed the chaos. The Nono had sent the Varia over with the singular purpose of trying to get the Family to bond since everyone had memories of the battles they had fought together in the future, and was hoping that the two sets of Guardians would get along better. Needless to say, it wasn't working.

All of Tsuna's Guardians were here, even Hibari. The prefect had shown up, the commotion having caught his attention, and was alternating between threatening to bite everyone to death and biting Mukuro, who had originally come as Chrome, to death.

Belphegor and Lussuria didn't seem particularly adverse to spending time in the Sawada household, especially Belphegor who seemed to be doing everything humanly possible to drive Gokudera up the wall. On the other hand, Lussuria seemed to have taken a liking to Ryohei and was currently hitting on the oblivious boxer.

The rest, even Xanxus who was currently sitting at the dining room with his boots on the table, a bottle of alcohol from Iemitsu's liquor cabinet in his hand, and the darkest sneer he could muster on his face, had followed for one reason and one reason only. Timoteo was expecting a report about all of them today and then a week from now. Reborn suspected that Xanxus was hoping his father would relent and call them back to Italy within a week if the Varia were on their best behavior – as best as the Varia could ever be – when the Nono checked in.

Reborn rather doubted it.

"It is very lively here today," Fon remarked as he jumped up beside Reborn.

"Lively isn't how I would describe it," Mammon said from Reborn's other side, having bowed out of the pandemonium a while ago. "I'm not even being paid to put up with you people."

Reborn just smirked. "It'll be good training for Tsuna. He can't be a good boss if he's afraid of his own men."

Mammon tilted his head and Reborn got the impression that the illusionist was looking at him from under his hood. "You better not let my boss here you say that. I'm not paying for any damages done to this house."

Reborn opened his mouth to reply and then shut it again when his senses picked up danger. He wasn't the only one. Even as Leon transformed into a gun, Fon and Mammon tensed and the Varia quieted unexpectedly, all reaching for their weapons. In his chosen chair, Xanxus didn't so much as twitch as he poured himself another glass of wine but his right hand was resting inside his coat pocket. The chill in the room was thick and heavy and even Ryohei picked up on the sudden tension.

"R- Reborn-san," While he hadn't reacted as quickly as the more seasoned Mafioso in the room, Gokudera had taken one look at the slightly pensive edge in Belphegor's maniacal grin and had reached for his explosives immediately. "What's going on?"

Reborn didn't answer, focusing on all the exits instead. There was nothing coming from the window or door or the rooms upstairs. Why did he feel so unsettled?

Abruptly, the air by the porch doors rippled before splitting, yawning open to reveal an endless black depth. Seconds later, they caught sight a glimpse of several figures coming through the portal.

Fon realized who the approaching forms were at the same time that Reborn did and both Arcobaleno leapt down, the former to usher I-Pin and Fuuta as far back as possible and the latter to position himself in front of the less-experienced teenagers in the room.

A heartbeat later, Mukuro knew as well and the illusionist stilled completely before melting back into Chrome. Reborn guessed that the teen knew it wouldn't be wise to be seen in the company of the people he had once tried to kill.

As the figures filed into the room and the portal snapped shut behind them, Reborn spoke up, his voice flat as the people behind him stirred uneasily.

"What business do the Vindice have here?" Reborn enquired carefully.

One of the Vindice, dressed in black robes and hat like the rest, stepped forward. His voice was a low rasp that grated against Reborn's ears.

"On the orders of our boss," The guard intoned. "We are to gather the Arcobaleno pacifiers. Any resistance will be futile and stopped at once."

A stunned silence ensued and even Reborn was taken aback. It was Mammon who asked the most obvious question, drifting warily above Belphegor's shoulder.

"Why?" The Mist Arcobaleno sounded as bland as ever but there was an underlying sharpness to his voice that everyone could hear. "It is the Arcobaleno's duty to protect the pacifiers. Not even the Vindice has a say in that."

"On the contrary," The Vindice guard countered coldly. "We have every right to the pacifiers. Hand them over."

"If you have no legitimate explanation," Fon interjected, still polite as ever. "Then we have no reason to hand anything over to you. The pacifiers are ours to protect."

"Then you leave us no choice," The guard returned, and in the blink of an eye, the Sawada household had turned into a battlefield.

Reborn didn't hold back as he fired at the nearest Vindice member, his jaw tightening when a black flame enveloped the man and deflected his shot.

"Stand back!" He barked at Tsuna's Guardians, glaring even Hibari into line and almost getting hit by a blast of energy in the process.

To his right, Fon was weaving around two guards while Mammon was facing off against another guard. Surprisingly, the rest of the Varia sans Xanxus had all joined in, though that might be because the Vindice weren't keeping their attacks focused on the Arcobaleno alone.

Reborn gritted his teeth and rolled out of the way of another explosion. He didn't know what the black flames the Vendice were using were but they were causing quite a bit of damage and were easily overpowering the flames being used against them.

As another explosion rocked the house, Reborn managed to intercept a stray blast aimed in Mammon's direction, whose illusions seemed to be doing little to no damage at all. At the rate they were going-

"Reborn, to your left!" Fon snapped from somewhere out of Reborn's line of sight. The usually calm Storm Arcobaleno sounded harried for the first time Reborn had known him.

Twisting around, Reborn fired off his signature attack and cursed in his mind when the black flames surrounding the oncoming guard's bandaged hand simply swallowed the yellow flames without slowing down at all. Reborn made to dive out of the way but hesitated when he caught sight of Mammon's unguarded back behind him. If he moved-

Bang!

A bullet flew by in front of Reborn and embedded itself into the far wall but effectively cutting off the Vindice's attack when the guard had to evade the shot. For a moment, Reborn thought one of the guards had pulled a gun in addition to the flames since no one on their side but him wielded actual bullets. It took another second to realize that even the Vindice had paused, the fighting dying down as all eyes turned to the newcomer standing by the front door.

And when Reborn saw who it was, his eyes widened.

"J- Jyuudaime?" Gokudera stammered out, dumbstruck by the man standing in the doorway.

Reborn scanned the brown-haired adult. Dressed in a crisp black suit with a white polo underneath and a black tie to finish off the ensemble, it was indeed his student who had fired off the shot. Arm extended and a black CZ75 held steadily in his hand, Tsuna was carrying a wide-eyed Lambo on his back and a school bag in his other hand, but his eyes, hardened to a burnished orange, were focused entirely on the Vindice, not quite glaring, but the unwavering stare he pinned them with, piercing and firm, refused to let any of the Vindice look away.

Reborn had no doubts that he was looking at a seasoned boss.

In the following silence, Tsuna shrugged his shoulders a little and Lambo obediently slid off, landing behind the brunet with a soft thump.

"Lambo, go to Hayato," Tsuna ordered, his voice coming out in a smooth tenor as he pushed the school bag into the boy's hands and gently urged him in Gokudera's direction.

The cow didn't hesitate, hurrying over to the bomber who promptly shoved the Bovino behind him with I-Pin and Fuuta.

Reborn barely spared them another glance as his gaze remained on the future Tsuna who was now advancing into the room, footsteps silent as he entered.

"Vongola Decimo," The guard who had spoken to them earlier and the only one of the Vindice who hadn't joined in the fight now turned to fully face Tsuna. Reborn couldn't help tensing further.

But Tsuna didn't seem particularly perturbed, only inclining his head in the barest of acknowledgements. He made no move to lower his gun and when he spoke, his voice held a note of ice that cut through the room with singular intensity.

"Do the Vindice no longer abide by their laws?" Tsuna started without preamble. "Going so far as to attack the Vongola Famiglia now?"

"We are here for the pacifiers," The guard responded harshly. "We gave them their warning."

"The pacifiers belong to the Arcobaleno," Tsuna countered evenly. His eyes flickered briefly over the each of the Vindice's bandaged faces. "The current Arcobaleno."

Reborn frowned. The current Arcobaleno? Why would Tsuna make that differentiation?

The guard didn't refute this claim. Instead, he took a step forward, placing him only a few feet away from the brunet.

"You may be the Vongola Decimo," The guard rasped. "But we will not let anyone stand in our way. It seems the Bovino's invention has brought you back from the future, but rest assured, you will stand little chance against us. The Arcobaleno are not under your jurisdiction. Let this matter go and move aside."

Tsuna didn't falter, taking a step to the side so Reborn was now directly behind him. Reborn raised an eyebrow and tugged down his fedora to hide his surprise. The Tsuna he knew would have backed down a while ago, panicked and stammering, stepping up and speaking against the Vindice only when they made another attempt for him or Mammon or Fon again.

"On the contrary," Tsuna retorted impassively, gun now levelled at the head Vindice's chest. "Ten years in the future or no, I am Vongola Decimo and this is my Family. The Sun Arcobaleno Reborn is part of the Vongola Famiglia and my most trusted advisor. The Mist Arcobaleno Viper is part of the Varia and most definitely under my jurisdiction. And the Storm Arcobaleno Fon is my representative to the Chinese Triads. All are under my protection."

He paused and his eyes narrowed. "No one attacks my Family and gets away with it. Not even the Vindice."

Reborn was quite sure half the room wasn't breathing. He himself watched the exchange cautiously. Going against the Vindice, no matter the reason, should not be done lightly, and his student – former student – had just done exactly that in the name of three Arcobaleno.

"...my most trusted advisor."

Reborn couldn't help the thrum of warmth that swelled in his chest as those words echoed in his mind. Working under this man, straight-backed and resolute and willing to face down one of the most powerful forces on the planet without batting an eye, wasn't something he could bring himself to mind.

In the next moment, Reborn sensed more than saw the signal and though his gun was already raised and pointed at the assailant almost before the man could move, he had no time to call out a warning as the Vindice guard on the right attacked.

It turned out Tsuna didn't need his help anyway.

Twisting to the side, his former student dodged the fist of black flames aimed at his throat, grabbing the wrist as it flew by and jerking it forward to yank the guard off his feet. Then, without stopping, Tsuna whirled on the spot, using the guard's momentum to throw the man across the room. The guard crashed straight through the porch doors, shattering glass everywhere as he slammed against the railing with brutal force.

Tsuna didn't stop there. While there were a lot of dropped jaws all around the room, Reborn had already shoved his own mild surprise out of the way and focused his gun on the second guard advancing on Fon. Once again though, Tsuna had already seen through the joint attack and a single bullet flying through the air and just missing the man's bandaged face stopped the guard in his tracks.

And he still hadn't activated his flames. Reborn could admit to being a little impressed and more than a little proud.

"That was your second warning," A thread of inflexible steel had entered Tsuna's voice. "There will not be a third. Get out of my house."

For a long minute, the head Vendice guard remained silent, not so much as glancing at the guard Tsuna felled. And then, with a flick of his wrist, the same portal snapped open behind him and the other guards took it as a cue to leave. One of them retrieved the guard on the porch before stepping through, leaving only one behind.

"Our boss will hear of this, Decimo," Was all the guard said before disappearing as well, black robes flapping behind him as the portal closed behind him.

Dead silence descended on the room, all eyes glued on the future Tsuna as the brunet lowered his gun and tucked it away before slowly turning to face them all.

"Well," Tsuna broke the silence, the orange softening to a familiar brown that still held a flash of flame in its depths. "This is quite a mess."

Like I said, it's just a half-formed idea. I'm not really sure what to make of this first chapter but I'll see where it goes from here.