Ben-10: The One True Monster

Author's notes: As usual, another fanfic with Ben getting displaced in another world. I skimmed through Ben 10 & Naruto crossover fanfics and realized that writers might have a hard time just throwing Ben into the universe. I did some research and planning beforehand and then I decided to challenge myself with this. Ben won't be replacing Naruto in this story, but rather I want to make a new perspective from which the story will be told. Without further ado.

— — —


Chapter 1: The Hopeless One

Alright, everyone, it's ready! Action, start!

Ahem. Welcome to the world of Shinobi — people with unbending will and wizard-like superpowers. I mean, they are ninjas, but for some reason, they have these awesome abilities, like blowing fire, etc. Those abilities aren't anything special in this world, but there is no My Hero Academia either. In any case, the shinobi have become the military strength of the countries.

This concludes our quick introduction to this logic-defying world because we don't have time to explain more about it so let's move on!

It took place in the Land of Waves. Trust me, "the Land of Waves" is the name of a country. Near a river bank, surrounded by trees, a group of three teenage ninjas (not mutant turtles) with their teacher were protecting an old man with glasses and fighting a guy who wielded a large sword, covering his face in bandages.

Hopefully, we can introduce them leisurely next time but for now…

Amidst the battle, the surroundings were completely covered in mist and fog, making them unable to see properly. A clone of this large-sword guy had trapped the teacher inside a ball of water, as he stood on the surface of the river.

Just then, an unexpected creature emerged— a large humanoid turtle-like being with a green hourglass-like symbol stuck on its torso surrounded by eight holes in its shell. With a graceful maneuver, the turtle hovered mid-air, transforming its limbs into flipper-like blades that spun at a dizzying speed. The powerful winds it generated blew away the mist, thus revealing the creature into clear view, momentarily surprising both parties.

The swordsman paused, wondering if the turtle was someone's summon. It wasn't an ordinary creature indeed, but it didn't matter: he was prepared to eliminate anything in his path.

"Oi, Sakura-chan," the blond teenager whispered to the pink-haired girl. "What's with that turtle?"

"Maybe Kakashi-sensei summoned him," Sakura replied.

"Summoned?" The boy stared at the turtle, trying to figure it out. The black-haired boy next to him also scrutinized the creature, uncertain if it was a friend or foe.

"Summoning Jutsu," he noted. "But how?"

Because their teacher, Kakashi, hadn't yet escaped the swordsman's trap.

"Anyway, he might be on our side," the blond boy said optimistically. "He cleared the mist for us."

"We can't trust him just yet," the black-haired boy reminded him.

"Don't worry, you can trust me," the turtle said, reverting its limbs to their normal form. "Sasuke, Naruto, and Sakura. Protect the old man. I will bring back your teacher."

Despite the doubts of Sasuke the black-haired kid, the three listened to the turtle and took their positions, ready to defend the old man with him in the middle.

"That's settled," the swordsman declared, tightening his grip on his weapon. "You will be eliminated."

The turtle chuckled with confidence. "Try me."

But hold up. This story doesn't start here. We are going back all the way to where it should start.

- (Transition) -

"Benji."

Welcome to the world of Shinobi — people who possess unbending will and astounding strengths. Unique, strange, gimmicky, and powerful. All kinds of people exist around me. No, the world doesn't revolve around me, however. I am something of a failure myself.

"Tenzaki Benji, put down the book and listen."

Lowering the book, my gaze shifted to the young teacher in front of the class. In his early twenties, he stood there, dressed in a long-sleeved shirt and pants that covered most of his body. Over the shirt, he wore a sleeveless flak jacket, and his chestnut hair cascaded neatly in a ponytail. His other distinct feature was a scar running across his nasal bridge.

It was Iruka-sensei.

"Your grades are good and all but… the academy's teachers want to meet you after school. Is that alright?"

"It's fine with me," I replied.

Iruka-sensei had a tense expression until his lips quickly curved into a genuine smile.

"Good. And… everyone, now, look at the blackboard."

I slowly raised the book and hid my face behind it as the teacher continued his lecture.

After school, Iruka-sensei escorted me to meet a group of other teachers. Judging from their uniforms, some among them must be guests from the Medic Corps. Ah, I realized it was going to be a pain.

"Tenzaki Benji, listen," Iruka-sensei said with a serious expression. "I hate to break it to you,... but it's best if you…"

I was indifferent. I don't know how many times I have heard that in my life.

"... stop dreaming of becoming a ninja. Your academic performance has been commendable, ranking second only to Sasuke in our class. Moreover, your creativity with ninja tools has been impressive, and your versatility in using a wide array of them is remarkable. However, it is evident that when it comes to jutsu, you are..."

He sighed and looked down at the documents, to avert his eyes from me.

"I know Tenzaki-senpai persisted to keep you in the Academy, thinking you might be a late bloomer. So it pains me to say this, Benji. You have…"

"I've heard enough, sensei," I interrupted him. "I understand what you mean."

"S-so will you step down?"

The Medic Corps must have spoken to him about my body being unsuitable for using chakra properly. I suppose I'm even worse than Naruto when it comes to jutsu, and he's considered the bottom of the class.

"I don't have a choice, right?"

"Sorry, Benji. You are dismissed for now. I will talk to Masato-senpai later, and the graduation ceremony is tomorrow. You might want to see your friends graduate, right?"

"Of course."

With a graceful stride, I, Benji Tenzaki, departed from the office.

— — — —


Family name - Tenzaki (天崎), given name - Benji (弁次).

Benji Tenzaki tiptoed into his house and dropped his backpack quickly in order to rush out again for his personal "training." But this didn't go unnoticed by Masato Tenzaki, who was sitting on the roof.

"Oi, Benjy!"

The boy who had just stepped out of the house flinched and turned around to find Masato. Benji was pretty certain Masato wasn't home, but the man was sneakier.

Masato Tenzaki (天崎 雅人), a handsome man in his mid-30s with a slight tan and a muscular build, wore an unbuttoned red Hawaiian shirt adorned with floral patterns over the standard uniform issued for ninjas of the village. His uncombed black hair was probably part of his charm, too.

"H-hai…" Benji was more than surprised but he had become used to it.

"... don't be late tonight," Masato reminded in a soft tone.

"I don't want to hear it from you," the boy almost yelled back.

That was normal, too. Masato was always the one to come home late. He was never the type of man to go out of his way to pick girls up, but somehow, ladies seemed naturally drawn to him in different ways. The boy could never fathom just how many girlfriends Masato had. And without a doubt, that aspect of his housemate bothered him.

Masato watched Benji's back as the latter ran along the road until he suddenly disappeared with a trace left… as he always had done. As an experienced shinobi, Masato felt shame for not being able to figure out how Benji could slip away from his sight.

Benji has always been like that. And Masato is probably one who is aware of this fact.

On the other hand…

"Tsk."

Benji suddenly appeared in the woods outside the village, dressed up in his uniform of choice, consisting of a white shirt with a black stripe, over which was a black long-sleeved jacket with dark green lines, and fingerless gloves, plus dark green trousers and black boots.

He didn't have an outstanding look. His hair was brown— messy and unkempt, a habit he inherited from Masato. His emerald green eyes might look special, as if they were capable of seeing in the dark or emitting light rays… or might have super abilities like Sharingan and Byakugan of distinct ninja clans. But no, they were just an ordinary set of eyes.

"... I don't like it," Benji was frustrated and annoyed, which was a given.

He acted like he didn't care in front of his teacher, but deep down, he knew he didn't want to accept it just as it was.

That's the reason Benji is here in the woods anyway.

"Omnitrix, scan the surroundings."

Benji whispered to no one as he rolled up his left sleeve to reveal his wrist covered in bandages, which also concealed a lump underneath.

They are fresh and clean by the way. Trust me, he washed them regularly.

With a quiet beep, the lump in the bandages flashed the green light for a short second. Benji had his eyes all over the surroundings, making sure no one was around. He doesn't have sharp instincts any shinobi would possess, unfortunately.

"Alright, no one's around," he noted and started undoing the bandages, rolling them into a messy ball as the device on his left wrist was gradually revealed.

It was the "Omnitrix" in question, a device that looked like a modern digital watch, with a square-shaped faceplate on which a green symbol was branded. That symbol should resemble an hourglass… I mean, it's an Omnitrix after all.

And then subsequently a few holographic monitors were projected from the Omnitrix, indicating the statistics, documents, and images alongside a holographic keyboard that floated right before Benji. The boy started running his fingers on the keyboard, keeping an eye on the screens… And this is what he calls "training."

It's not training. He's actually trying to find out how to strengthen himself using the Omnitrix, without scaring others. Because he is…

Meanwhile in the village head's office…

Two people. One was Masato Tenzaki, and the other was an old man smoking a pipe as he sat at the table.

"How is he doing, Masato?"

The old man had a dignified and clear voice, almost indicating his strength despite his age.

Masato nodded. "As always, he is showing impressive athletic abilities, Hokage-sama. But his chakra-related abilities…"

"Didn't improve, huh?"

Hokage-sama. "Kage" is the title given to the strongest ninja in the ninja village. In Konohagakure, this old man, dressed up in a traditional, exquisite attire consisting of a white robe and a hat, bearing a white beard, is the Kage— who also serves as the village head.

The title "Hokage" is exclusively for the "Kage" of Konohagakure no Sato, the Village Hidden in the Leaves, and in fact, this old man who might be past his retirement age, is the third Hokage since the foundation of the village.

Well, this is enough for the introduction.

"Yeah. But his physical capabilities are always extraordinary. I think he might even be stronger than adults, and even without Chakra, he can use shuriken and kunai properly."

"Masato."

Masato fell silent as the old man cut him off, wearing a stern expression with a hint of almost glaring intensity in his eyes.

"Even if you say so, we can't just let him become a Shinobi," Hokage said in a stony cold tone. "He is like a son to you, right? He would die, Masato. His safety… His life. They take priority. You better keep that in your mind."

Masato nodded, finding himself at a loss of words.

"I understand, Hokage-sama."

"Great."

At that moment, a shinobi rushed into the office, gaining the two's attention.

"We have a problem, Hokage-sama!"

"Hmm?"

"The sealed scroll of the forbidden has been stolen as a joke… by Naruto!"

Masato looked back at the old man, who wasn't fazed at the information.

Hokage didn't even pause his smoking as he calmly responded. "Gather the shinobi."

"Roger!"

When the shinobi quickly left the room, the two also followed shortly after to meet up with the village shinobi.

"Isn't it like a big deal?" Masato asked, confused at why the old man was so calm despite that.

"It's been half a day since that kid's got it," the old man replied. "I knew that before they noticed. By the way, Masato, where does your kid train now?"

"... huh, why, Hokage-sama?"

"No particular reason."

- (Transition) -

"Dang, I still can't find a way to sort this out at all. Too bad I never learned genetic science."

Mumbling out of frustration, Benji decided to call it a day and closed the monitors. He couldn't find a solution today, either. It sucked.

Speaking of which, what is this "Omnitrix", you wonder?

Omnitrix is a device that has been stuck on Benji's wrist for who-knows-how-long. Masato is aware of it, but he couldn't figure out how to get it off. Third Hokage inspected it and considered it harmless for the time being, thus the Omnitrix has remained there till now.

Omnitrix does many things but tells time. Benji has examined the device in and out, and he's discovered a ton of its features. Yet there is still a lot he hasn't found out. Primarily, the Omnitrix is a device that can modify the user's DNA.

"Can't you just do something, huh, Omnitrix?"

That's why Benji thought the Omnitrix could change his DNA and repair his anatomy so he could utilize the chakra properly. If he ever finds a way to manipulate his DNA without failing, Benji might well become a powerful shinobi.

By the way, another known function is teleportation, which Benji used to escape the village to the woods.

But it's still just far from becoming reality, I guess. I'm beat.

Benji wouldn't have guessed he was missing a major function of the Omnitrix.

"Beep."

"...hmm?"

Benji knew someone entered his vicinity. They didn't seem to notice his presence, fortunately.

A kid of his age, with spiky blond hair and blue eyes, adorned with three whisker-like marks on either side. The orange jumpsuit he wore, with a fiery red symbol on his back, was almost a trademark of his. He also wore a pair of goggles on his forehead.

Naruto? He has a scroll on his back…

Benji did a quick landing and quietly followed Naruto Uzumaki from a distance until the latter finally stopped near a cabin.

The brunet speculated that the blond kid might be "training" (though not in the way he did), given that Naruto was at the bottom of their class. However, Benji was never one to pry into someone's business.

Should I watch him here? Or just move somewhere else? I definitely shouldn't disturb him.

For the kid he is, Benji so well knows to respect one's personal boundaries and privacy.

"Let's see…" Naruto muttered to himself as he carefully undid the sealed "Scroll of the Forbidden". "According to Mizuki-sensei, this scroll contains amazing jutsu. But…"

He was almost defeated just at first glance.

"Already a technique I'm bad at…" he groaned, seeing the description of a clone jutsu.

If Benji weren't someone terribly bad at ninja arts, he might have taken a peek at Naruto's scroll, out of curiosity, but Benji right now had little interest in the contents. Rather, he was invested in what Naruto was going to do.

"Kage Bunshin no Jutsu!" (影分身の術)

Shadow Clone Technique.

Sounds like a sibling of Clone Jutsu. Pretty cool…

Chakra escaped from Naruto's core and quickly accumulated next to him, forming a humanoid shape, which proved Benji's guess right. But sadly, before the scene could get Benji excited, the humanoid shape of Chakra quickly dispersed, leaving nothing behind.

Naruto couldn't keep the Jutsu long enough.

He then struggled, faced defeat again and again. But each time he fell, he got back up on his feet and resumed his training, persistently repeating the process. His clothes became dirty, and his hands gathered small bruises, yet he never gave up.

"This guy…"

I gotta admit, I never thought highly of this guy. Benji mentally noted.

He had always regarded Naruto as a loud, annoying, hyperactive kid, though he never particularly disliked him.

"It's so difficult," the blond kid groaned.

The brunet must agree it was difficult: even in the exam, Naruto failed to make a proper clone using the Clone Jutsu, thus failing to graduate. On the other hand, Benji is hopeless at it.

He actually related the struggle Naruto was facing.

"Even he is working hard…" the brunet quietly muttered to himself, looking down at the Omnitrix.

How can I be useful to others… and to myself? Then he found an answer by himself.

Concealed behind the tree, he activated the Omnitrix, summoning a single holographic monitor that displayed his own personal data. It showed DNA structures, cell structures, and his very being represented in numbers, graphs, and other visuals. He began to study it, his eyes almost glowing bright green as if they were going to absorb everything in their sight.

Maybe… maybe… I can do it, too.

Just like that, the two boys did their respective training in the forest, until they became absorbed in it that they didn't even care about the time passing.

"Beep."

Only when the Omnitrix made a quiet alarm that Benji came back to his senses. Someone else entered his vicinity.

"Log off," the boy whispered to the Omnitrix, closing the monitors.

The one who made the arrival was a white-haired shinobi, wearing the Konohagakure headband, carrying large shurikens on his back.

Mizuki-sensei. What is he doing here? No, wait, it's not just him.

Another one who came into view was Iruka-sensei, the teacher of Benji and Naruto.

Hmm?

Unfortunately, both teachers— two professional shinobi— were unaware of Benji's presence. Mizuki went into hiding as soon as he saw Iruka approaching Naruto.

"Oi, Naruto."

Iruka called out, landing before the blond kid, who was now taking a breather from training. The teacher looked like he searched for the kid all over the village, exhausted and panting.

"Ah, you found me…" Naruto quickly got up from resting and excitedly spoke to his teacher.

"I've only learned one Jutsu. Listen, listen! I'm gonna show you this amazing Jutsu. You're gonna let me graduate if I can do it. Isn't it true that I can graduate if I can do one of the jutsu written here?"

Something's off. The exam is already over, too.

"Who told you that!?" Iruka asked, surprised.

"Mizuki-sensei! He told me about the scroll and this place…"

Then Iruka suddenly pushed his student away as the weapons came out of nowhere and stabbed the teacher, pinning him on the wall of the cabin.

"I'm impressed you even found this place."

Mizuki-sensei, why did he…

Benji couldn't quite see Mizuki from his hiding spot but it seemed he was the one who threw the kunai at Iruka.

what is going on?

Thankfully, Iruka somehow managed to dodge the majority of Mizuki's kunai just in time so he only took a small amount of damage.

"I see now… how it is," Iruka said, panting as he looked up at the white-haired teacher.

"Naruto, give me that scroll," Mizuki ordered the confused Naruto.

Iruka pulled the kunai out of the wound. "Naruto, never give him the scroll."

Man, I feel like I shouldn't get involved in this mess.

Benji noted, trying to assess the situation. Two experienced shinobi. One Naruto. If anything, Benji should rush back home. But one side of him couldn't let his eyes averted from the scene.

"It's a sealed dangerous object that contains forbidden ninja arts," explained Iruka. "Mizuki used you in order to get it for himself."

Ugh, this is more complicated than I thought. Benji silently monologued to himself.

"Naruto, Iruka is only afraid of you holding that scroll," Mizuki made an explanation himself.

Naruto looked troubled.

"What are you saying, Mizuki!? Naruto, don't let him fool you." (Iruka)

Benji would react the same way as Naruto did if he were in the same position. But it was harder to believe Iruka would tell a lie without a good reason. Call it a bias or whatever.

Mizuki laughed. "I will tell you the truth about you."

"Idiot, don't do that!" Iruka looked freaked out.

"After the incident twelve years ago, a rule was created. Naruto, that is a rule everyone but you know."

"Except me!? What kind of rule is it!?" Naruto exclaimed.

"Stop it, Mizuki!" (Iruka)

Benji gazed at the blond boy. Is there such a thing? Ahhh, I don't know if I should be here eavesdropping on them! Is that even morally right?

But… screw it, I am listening.

Benji couldn't beat his own curiosity. He won't for sure beat Goku that way.

"It is, nobody is allowed to talk about the fact that you are the Demon Fox."

Hmm, what's a demon fox again? Benji's focus shifted to the blond kid, who seemed to be at a loss of words.

"Huh? What do you mean?" Naruto muttered.

"Stop it!" Iruka was still trying to stop Mizuki.

"It means," nothing was stopping Mizuki. "That you are the Nine-tailed Fox that killed Iruka's parents and destroyed the village!"

Benji didn't expect to hear that.

"... You were sealed up by the Hokage you admire, and you've been lied to by everyone!"

I couldn't quite follow that one. What. Like, what the heck.

Benji recalled Masato telling him about the Nine-tailed Demon Fox's attack on the village. The Fourth Hokage sacrificed himself to save the villagers, but Masato never revealed the exact details to the boy. Benji was left hanging, never knowing the end of the story or what ultimately happened to the Demon Fox.

"Nobody! Will ever accept you!" Mizuki claimed like he was mentally attacking the blond kid. But he actually was.

"No, no, no!" Screamed Naruto, bursting with emotions.

Benji had three sides— was shocked to hear Naruto was the Demon Fox— and felt bad for Naruto who had been shunned by the village folk for that reason all his life. He could never imagine how frightening it would be to learn such cruel truth.

But this is not my place to meddle in. Benji took a step back and turned around, quietly retreating into the forests.

"That scroll was also used to seal you up!" Mizuki yelled, spinning his large shuriken on his hand. "Now, die, Naruto!"

Naruto tried to get out of the way but stumbled on his own feet and fell over.

"Naruto! Get down!" Shouted Iruka, rushing to the kid, as Mizuki threw the shuriken.

The teacher intercepted it just in time, shielding his pupil with his own body.

Benji stopped in his track, and couldn't help turning around for a glance at the scene. The large shuriken had stabbed Iruka in his back.

"... oh, no."

This is bad, right? Should I go find other shinobi in the village? Or I can just drag old man Masato here… What should I do?

"Naruto, you must have been in a lot of pain, too," replied Iruka, tearing up. "Just like me. I'm sorry. If I had done a better job, you wouldn't have had to face this."

At this point, Benji really didn't know what to do… He'd given up, but he decided to watch the three for the time being.

I know I need to get Masato-nii here, but… Tsk, I won't get him in time. Damn it.

Hearing Iruka's words, Naruto took a glance at Mizuki and started running away from the two teachers.

"Naruto!" yelled Iruka.

"Hehehe, sorry," Mizuki said with an almost evil grin. "Naruto isn't the type to have a change of heart that easily. He sure plans to use the scroll to get revenge on the village."

Mizuki smirked and used Transformation Jutsu on himself and chased after Naruto, leaving the injured Iruka behind.

"Crap," Benji decided to quietly follow the two until he saw the injured teacher getting up and running in a different direction.

He's not running after Naruto?

Much to the surprise of the brunet kid, the transformation jutsu on Iruka wore out and it turned out Iruka was Naruto in disguise.

Whoa… this is kinda amazing. Which means Naruto is…

Naruto tightly hugged the scroll in his arms as he ran into the forest in order to hide from Mizuki. Till now, no one had caught Benji's presence, fortunately. He had taken a step up and started following Naruto from a safe distance.

When the two kids caught up to their teachers, Iruka had already exhausted himself. The wounds were still fresh… At this point, protecting Naruto and the scroll of the forbidden from Mizuki took priority. Iruka understood it was as far as he could go.

"Hehehe," Mizuki's laugh didn't sound sweet to the kids' ears.

"You'd even transform into what killed your parents to protect him?"

Iruka glared at Mizuki. "I won't hand over the scroll to an idiot like you."

"No, you are the idiot here," said Mizuki. "Naruto and I are the same. If you use the skills in that scroll, you can do whatever you want. There's no way Demon Fox wouldn't do that!"

Benji's gaze shifted toward Naruto who was curling up behind the tree.

"Yeah, Demon Fox would do that. But Naruto is different. I've acknowledged him as one of my excellent students."

WHAT ABOUT ME? Benji screamed internally. That's a joke, thanks.

"He may not be the hardest worker. And he's clumsy so nobody accepts him. He also knows what it is to feel pain in your heart. He's not the Demon Fox anymore. He's a member of Konohagakure, Naruto Uzumaki!"

Iruka-Sensei really loves Naruto, huh… Benji glanced at Naruto who was silently crying.

"You're so gullible, Iruka… I thought I would take care of you later," Mizuki said. "But I've changed my mind. You'll die here and now!"

Benji didn't have a chance to have a second thought.

Oh, no you are not— wait, what the heck am I doing!?

Having taken a position on the tree to interrupt Mizuki, Naruto widened his eyes in surprise witnessing Benji suddenly come out of nowhere.

"No—"

But that went fast.

Iruka was ready to embrace Mizuki's attack if that would stall the chase after Naruto. But his weapons never reached Iruka…

"What's going on!?" Iruka exclaimed, seeing a kid before him.

That kid who had been struck by a large shuriken. Mizuki himself didn't see that coming.

"... At least… I," and so Benji dropped to the ground.

At least, I got to save someone.

"This is…" Iruka recognized the boy. "Benji."

He dragged himself toward the boy and pulled him toward himself, but after a quick glance, he realized Benji wasn't going to survive such a big wound.

"Tenzaki Benji? Another stupid kid," Mizuki glanced at his now-blood-stained weapon. "Whatever, Iruka, I will end your life first and go after—"

"As if I would let you!"

Naruto threw himself at Mizuka and kicked him as hard as he could, sending the teacher flying.

"How is he, sensei?" He took a quick look back at Iruka.

"He's…" Iruka didn't need to spell it out. Benji's body was already lifeless.

"..." Why did he even get in there…

Naruto put the scroll down near Iruka and glared at Mizuki who just recovered from the fall.

"If you ever lay a hand on Iruka-sensei, I will kill you!"

"I can take care of a kid… or two without a sweat," Mizuki mocked. "Ha… already done that to one."

Naruto took a glance back at the lifeless Benji and then made a hand seal to activate the jutsu.

"He gave his all to save sensei. On his behalf, I will strike you a thousandfold. Shadow Clone Technique (Kage Bushin no Jutsu)!"

- (Transition) -

From now on, this part will be narrated from Benji'sperspective.

My perspective? Give me a break, it's going to be embarrassing. I just died, too. I died again. Again? How many times have I died? Is it even possible to die more than once?

What's even going to happen to me, huh, Omnitrix?

At least, I saved Iruka-sensei, at the cost of myself. Reminds me of what Masato-nii told me when I was a kid. I mean, I am a kid now, but I was a younger kid back then.

"You know what, Benji? You simply can't tell what kind of person they are just after you meet someone. You can make a guess and go along with it, but still, your judgment will be shallow."

Oh, I still remember a memorable flashback that we were lying on the roof after a warm evening. We stared at the stars and the moon, too.

"As shinobi, we can't avoid our duties. Our missions often involve infiltrating organizations, governments, or even the military. That's why we must train diligently to become wise judges of people, assessing our enemies' strengths and facing tough challenges."

"Mm," I feel like I am still bad at assessing people.

Masato likes to talk a lot with me when he doesn't go out to drink or meet girls.

"Speaking of judging people," he changed his tone. "Benji, you ever heard of "hero syndrome?""

"No, I've not."

Masato smiled. "Hero syndrome is when someone desperately wants to help others despite their powerlessness."

That was a pretty solid definition, and as a kid, I didn't understand it instantly.

"Powerlessness?"

Masato looked uncomfortable. I guess he felt bad mentioning it because I was essentially a powerless failure among other superhuman shinobi.

"One needs to understand the limit of themselves to survive in this world," he answered. "Powerlessness doesn't necessarily mean you have no power. You're only truly powerless when you feel like everything, even nature, is against your favor and you can't turn the tables."

"So it is the same as "hopelessness," right?"

Masato chuckled. "You've really grown in such a few years. You're right. Powerlessness is like hopelessness. It's when you can't win no matter what."

"I see."

Masato gazed at the moon. "Speaking of hope, do you think the moon could shine if there wasn't the sun?"

"Um, no? Because the moon reflects the sun's light to the earth."

"Indeed, allow me to present a metaphor. Consider the sun, our sun; it represents hope. Now, envision yourself as the moon. Without the sun, you cannot generate light. Similarly, achieving anything without hope would leave you empty, even if you manage to accomplish it."

Masato isn't really a good speaker. This is almost embarrassing. Sounds like something outright ripped off from some media.

We stayed silent for a moment as I failed to find words to reply with.

"... That's why hope is important," he picked it up. "Sometimes, you need to recognize your limits too. Surviving as a shinobi is tough. I'm not trying to stop you, but if it becomes too much, it's okay to let go. You don't have to be a shinobi. There are many other paths to survive."

You are right, Masato-nii.

Why sacrifice yourself to save someone if you're not certain they'll be protected in the end?

The flashback has ended. Now I've got nothing but this empty, cold, lonely, and endless darkness.

"It's not the end yet, Tenzaki Benji."

Who's speaking!? I'm dead, right? So is it death speaking to me?

"I am you. Well, you used to be me, but it seems you are someone else now."

Oi, please speak a comprehensible language.

"For your question, yes, you've been dead before."

What do you even mean?

"Open your eyes. Let me show you who you are."

I'm dead. How am I… Wait, turns out I can open my eyes.

Amidst the complete darkness, an enigmatic humanoid figure stood a few meters away from me.

I could see my hands and move my body somehow. I don't know where I am, but I don't feel alive either.

"Who are you?" My voice was clear but shaky.

Lights from nowhere brightened up the surroundings, revealing him clearly.

A young man. He might be a bit older than me, perhaps 16? 17? He was handsome and had brown hair and green eyes like I did. Out of all, his green jacket was quite distinct.

"Benjamin Kirby Tennyson," he stated his name.

A name I've never heard before, yet it feels strangely familiar.

"So what are you? Are you God? Angel?"

Benjamin grinned, holding back his laughter. "No, I'm nothing that great. Alright, I will tell you about myself. Oh, it's also about yourself."

- (Transition) -

Iruka's gaze fixed on the lifeless Benji. "How do I apologize to Masato-senpai?"

After knocking out Mizuki using his shadow clones, Naruto returned to Iruka with a somber expression.

"Sensei, let's go back."

"... Yeah…"

But at that moment, a miracle occurred.

"Wait, sensei… Benji is…"

Upon hearing Naruto's words, he looked down at the brunette kid and had to cover his eyes because of the bright green light coming from him.

"What is going on!?"

Iruka and Naruto jumped away from Benji's body as an instinctive response. But before the two could process what was happening, the light quickly died down and revealed to the two that Benji's wounds had been miraculously healed by a mysterious energy.

"Don't get close to him, no matter what," the teacher alerted his student, to which the latter responded with a nod.

Iruka himself slowly approached the body and carefully tested Benji's life sign, which confused him.

"He's alive," said Iruka as he continued inspecting the boy.

How could that be? He was sure the boy was dead. With that amount of blood loss and grave wounds, a kid couldn't survive. Before long, Benji started breathing like a normal person.

"Naruto," the teacher requested. "Could you please watch over him? I will bring medic-nins (medical ninjas) and other shinobis here. The village shinobis are mad about you so I can't send you on my behalf."

"Leave him to me, sensei!"

Iruka himself was injured, but as soon as he met someone from the village, it should be fine. Naruto observed his teacher vanish in a blur and then turned his attention back to Benji.

"Oh, you scared me," Naruto almost cursed himself when he saw the brunet awake, his eyes wide open.

"So I'm alive," Benji immediately sat up from lying down.

"Okay, I'm not sure you should just sit up like that. You're really injured."

The blond boy honestly didn't know what to do. But Benji chuckled, glancing at the unconscious Mizuki in the distance. "Don't worry about that. I'm completely fine. But where is Iruka-sensei?"

"He went back to the village to get medic-nins for you."

So it seems sensei is okay, too. Sighs.

Benji then remembered what he overheard about Naruto during the exchange between the three.

What should I tell him? Oh well, I should just leave it as it is. It might be insensitive to get involved in his personal matters.

A few minutes he died felt like a week to him.

Soon, Iruka returned with several shinobi and medic-nins to where the kids were. After examining the kid, the medics confirmed Benji was fine, but Iruka insisted on getting him hospitalized for the time being. On the other hand, he had to clear the village's suspicions about Naruto. He knew some shinobi might be wanting to kill off the kid.

"I have to meet Hokage-sama."

- (Time Skip) -

Masato honestly didn't know what expression to wear when he met Benji on a hospital bed.

"I said I was completely fine, but they put me in this anyway," the kid whined, raising his cuffed hands. "They ran all the check-ups and found I'm healthy. Still won't let me off."

The older Tenzaki realized he might end up paying unnecessary bills, but it wasn't a big deal. He had heard what happened from Iruka, and he was willing to cover everything to save the kid.

"Ah, I bought some apples for you, by the way," Masato placed a basket on the table.

"To keep the doctors away?" Benji joked.

"Yep, haha," Masato played along, but what Iruka had told him still bothered him.

A while ago, he met the Third Hokage and Iruka in the Hokage's office. It seemed the teacher had something important to discuss, which he assumed was related to Benji's academic issues. However, it turned out to be something far more significant.

The Hokage appeared quite serious too. That old man was almost apathetic when Naruto stole the forbidden scroll.

"Jonin Tenzaki Masato reporting, Hokage-sama."

The old man nodded. "Tell him, Iruka."

"Hai, Hokage-sama," the teacher directed his attention to Tenzaki. "The thing is…"

The Third Hokage was already aware of the incident in the forest even before Iruka's report. After letting Masato know about it, the atmosphere in the office became more intense.

"In my long life, I've witnessed and studied countless jutsu," spoke the old man. "Some defy human comprehension, while others showcase remarkable feats based on one's abilities. However, there are forbidden jutsu that humans must never meddle with, like attempting to revive the dead."

"..."

"Iruka, are you sure the kid was…" the old man asked.

"I… I confirmed. He was gravely injured and lost a great amount of blood."

A moment of silence enveloped the three. Even if such a jutsu existed, they were well aware that Benji was the last person capable of wielding it. Even supposing Benji could do it, it would take a large amount of chakra. A dead person wouldn't be able to cast it on oneself in any way.

"What do you think, Masato?" Asked the old man.

"I think it's the Omnitrix's doing, Hokage-sama," Masato commented.

The old man nodded. Iruka was also aware of the device but none of them knew the details.

"I'm glad that your kid is fine, Masato. And we confirmed that the device wasn't harmful to him at all. Still, we can never be too careful."

"I understand, Hokage-sama."

"Alright, you're dismissed for now. You should spend time with your kid, Masato."

"Hai…" What actually happened to you, Benji…

- (Transition) -

Benjamin Kirby Tennyson. I used to be known by that name about 12 years ago. I used to be a big name, according to these memories I've recovered. But… my life as Ben Tennyson wasn't that beautiful.

"The Omnitrix has a far more important function than the ones you've discovered," explained my past self to me. "You will probably find out soon even if I, your memories don't tell you."

The Omnitrix's primary purpose is to store genetic data of extraterrestrial species in the Solar System. However, its research reveals no such life in this world. Still, one of its key functions is transforming the user into a chosen species. So, I suppose using it for myself shouldn't be an issue, right?

Turns out I've been using just a few minor functions of the Omnitrix. How can I discover the major ones in the past half of the decade?

"Regaining memories is a crappy experience," I commented, causing Ben to laugh.

"But I'm surprised you didn't break down or something. You are one strong kid, Benji."

"With these past memories, I'm not a kid anymore, right?" I sighed. "I see I've suffered much more in my past life. It would be laughable if I had a breakdown just because of memories."

"Ha…"

Okay, apparently, the functions he mentioned were locked behind a series of several processes by my past self.

"Also, make sure you hide the true nature of your powers," he reminded me. "Make it seem like you are using a jutsu, well, since shinobi people use it, right?"

"Yeah…"

"Give it some time. At any rate, I will leave the rest to you. You can use your powers… the way you want. And I'm pretty sure you know what to do."

My life story as Benjamin Kirby Tennyson wasn't beautiful.

"Yeah, of course."

I am taking notes from my past self and going to write a beautiful story of my life. I need to be useful.

Now back in the present.

I made some adjustments to the settings of the Omnitrix. Thus, when I tap or press the faceplate of the watch, it will show me a holographic circle displaying the symbols of the species I have access to. For now, I'll only touch the ones I've experienced in my past life.

"Maybe I should give them new names? I am Japanese now so it doesn't feel right to call them by English names…"

Above anything, it would be awkward to call them with my Japanese accent.

Scrolling through my roster, I smiled upon seeing one of my favorite forms.

"Long time no see, my old friend," I released the faceplate, causing it to slide down for the core to pop up. "Henshin!"

Ah yes, the green light. I'd not transformed in a long time so it definitely felt great and nostalgic.

I became taller after the transformation. My arms had turned into massively buffed crystal limbs with unbreakable fingers. Skin color was greenish blue, with no racism intended toward petrosapiens. If I have to describe the shape of this form, I'd say it quite resembles a humanoid crystalline golem, with a few pairs of crystal spikes on its back.

I call this form "Diamondhead."

"Hmm, let's see," I generated a few small crystal shards in my palm. "A creature made of a substance that looks like diamond…"

"不壊宝石" (Fue Hōseki lit. Indestructible Gemstone)

So if I transform in front of my friends and foes, it'll be like—

"Oi, Benji, we are going to the diner."

That surprised me! I didn't hear Masato-nii knocking on my door.

"We're having steaks tonight. Come on, hurry up."

"Hai, I'm almost—" wait, I fked up. I forgot to transform back to human form.

"That voice. Who are you!?" He yelled worriedly. "What are you doing—"

Most aliens don't share the same voice with me, which is why everyone's going to think it's a different person from the voice alone.

HELP ME, OMNITRIX!

I could hear the door lock undoing but fortunately, I got detransformed just in time.

The door slammed open violently to reveal a busy Masato Tenzaki looking all over the room with a worried look.

"Was there any other person in the room?"

"No, it's just m-me," I skipped a beat, stuttering. "Why?"

"Maybe I misheard that," he looked confused. "You ready?"

"Yeah, I am."

Masato gazed at my hands that were holding the crystals I just made.

"What is it in your hands?"

"Oh, uh, nothing special," I immediately unclenched my hands, hoping he wouldn't get suspicious. "These are crystals I picked up, uh, somewhere in the village."

"Benji, you," he sighed. "You don't grab random things off the street. It coulda been something dangerous."

"Hai, wakarimashita, now please let's head to the diner, shall we?"

At least there is no issue anymore. I better be more careful.

And so some time had passed since Benji was discharged from the hospital.

His classmates from the Academy, including Naruto, had graduated as Genins. Now they've become basic-level shinobi who can take on missions.

He didn't become a Genin himself, so he must take time to consider another career. It would be a different story if he had even little control over his Chakra. That way, it would have been possible for him to pursue the Shinobi way.

"Alright…"

But for now, he has to take a step back to see what he should do.

The boy wrote a letter for his guardian and left home for a break. The older Tenzaki seemed to be out on an errand.

"Then, Ittekimasu." (行ってきます)

Meanwhile three of his former classmates– Naruto, Sasuke Uchiha and Sakura– with their assigned team leader Jonin, Kakashi Hatake, were preparing to go on a mission outside the village. Their mission was to escort a drunk old man back to his town.

"You see, I've never really left the village!" Of course, Naruto was hyperactive as always.

"Oi, am I really okay with this squirt?!"

"Don't worry," Kakashi said politely. "I am a Jonin watching over the team."

Hmm, interesting. Benji was peeking at them from the forest, but he almost got caught by Jonin Kakashi.

Kakashi is a man in his mid-20s, with a tall and lean build, his silver spiky hair covering his forehead protector. A mask conceals his nose and mouth, and he wears the standard Konoha Jonin attire with a pair of open-toed sandals.

"What is wrong, Kakashi-sensei?" Sakura asked, seeing him gazing into the forest.

"Nothing special," Kakashi said, shrugging off the feeling.

"I'm a super elite shinobi who will be the Hokage one day! My name is Naruto Uzumaki, remember it well!" Naruto claimed, pointing his index finger toward the old man.

In the forest, after barely avoiding being discovered by Kakashi, Benji activated his Omnitrix to transform into one of his aliens. Namely, Ghostfreak. A ghost-like alien with an eerie, shadowy, gaseous body, with a single eye and claw-like hands. The Omnitrix symbol peeks out of the crack in his chest.

Immediately after transforming, Benji dispersed himself and turned invisible to tail along Naruto and his pals without their knowledge.

"I'll never acknowledge you, squirt," the old man said, angering the blond kid. "Even if you become the Hokage."

"Wha!? I will kill you!"

"Stop it, you moron," an annoyed Kakashi grabbed Naruto by his collar to restrain him.

Seems like a pain to babysit someone like Naruto. Benji mentally commented. Hmm… who's there?

Ghostfreak sensed two presences in his vicinity. He flew toward the place, to find two ninjas hiding in the trees observing Naruto and his pals. Especially the old man. But Benji didn't know what the mission for Naruto's team actually was.

Moreover, these two ninjas looked dangerous. He didn't know how skilled Kakashi was, but he didn't feel it was right to leave it as it was… Like, what kind of person would let adults attack a group of kids?

Screw it. I am doing it!

"... in other countries, hidden villages exist and so do ninjas," Kakashi explained to the kids. They did not seem to be aware of their pursuers.

Two masked, shady shinobi, covered in black robes, jumped from one tree to another, following the team. Ghostfreak was right behind them, still thinking about how to fight off these guys… or potentially scare them for their lives. Benji was perfectly capable of doing either of them or both.

The symbols on their forehead protectors suggested they weren't from Konohagakure, but they didn't seem to be targeting the village. What is their goal?

"... only the heads of the five hidden villages can be a Kage," explained Kakashi. "They have supreme power over tens of thousands of ninjas in each country."

Meanwhile Benji the ghost had been observing the two shady ninjas setting up traps and hiding spots to advantage their jutsu. Preparing this much to fight a group of kids… wait, maybe Kakashi is a badass? He's a Jonin after all.

And so the team proceeded with their trip, with two pursuers and Benji looking out for them. He decided he would interfere only when needed, since this was essentially his first fight as an alien in this life. He wouldn't want to reveal himself that easily to the world, considering what happened in his past life.

Kakashi glanced at the puddle in the road and walked past it without a word. Ghostfreak, knowing a pursuer was hiding in the puddle of water for a sneak attack, had readied his hands out.

As the team of Leaf shinobi had walked away, the first pursuer silently came out of the puddle while another one jumped out of the forest, both throwing a chain-like weapon at Kakashi.

They are fast! Telekinesis.

Ghostfreak barely caught the weapons mid-air using his telekinetic grasp, however, surprising the two shinobi.

Ha, thankfully…

But he didn't stop at just the weapons; he extended his grasp and trapped the two in place. Their movements stilled, like statues caught in time.

"Hmm?" Kakashi looked back with his usual bored look, to find his pursuers unable to move. "Yo."

"Wha, who are they, Kakashi-sensei!?" The kids were also freaked out.

He raised a brow, sensing that someone else had captured these ninjas before he did.

"These two have been tailing us," he stated matter-of-factly. "But… I'm not the one who caught them. This is strange."

Trapped in Ghostfreak's unyielding psychic grip, the two shinobi wriggled and fought, their attempts to break free in vain. Ghostfreak was confident in his telekinesis. The chain weapons suddenly flew back toward the two pursuers, looping back in an uncanny dance and wrapping around them, pinning them to the ground.

Kakashi and the kids watched the scene attentively as the shinobi were now successfully immobilized.

"They are shinobi from Kirigakure," said the teacher. "These guys are ninjas known for continuing to fight no matter what the sacrifice."

"How were you able to detect our movements?" One of the shinobi asked.

"A puddle of water on a clear day like today when it hasn't rained for days," Kakashi answered. "But… never mind about that. Tazuna-san, you are the one they are targeting, right?"

He knew it was an invisible helper who captured these two shinobi. Uncertain whether this ally was on his side, it was useless to find someone so skilled in hiding that he couldn't even sense their presence at all.

"We haven't heard anything about you being targeted by ninjas," he looked at the old man, Tazuna. "The content of this mission is supposed to just be protection from gangs, thieves, and the like… If ninjas are involved, this is a B-rank or higher mission. It appears there is a good reason for this, but being lied to in the request won't do."

"So what are we going to do?" Sakura questioned. "Are we going back? A B-rank mission is too soon for us."

Sasuke didn't show an opinion on the matter, but Naruto didn't seem to be wanting to give it up. Kakashi took a moment to think, staring at the kids.

"For the time being, we will escort you to the town," he said. "We will discuss if we should drop the mission after that. I have questions for you, too, Tazuna-san."

He could easily handle this low-level type of rogue shinobi. And he wanted to find out more about that invisible helper.

"Th-thanks…" The old man seemed to be sober now.

Benji as Ghostfreak was still just around them. Ectonurites (Ghostfreak's species) are ghosts through and through, having no live life energy and thus, no chakra at all. He decided to follow the team for now, thinking he would see interesting events if he stuck around.

Meanwhile at Tenzaki's house…

Masato just returned home after finishing the errands, only to find a letter on the dinner table. He freaked out for a second, but quickly regained his composure to read the contents of the letter.

"... So I will be going on a vacation. Don't worry about me. I will return in the evening alive and well, I guarantee." Masato deadpanned. "What kind of child writes something like this and just leaves the house?"

Masato thought for a moment.

"Wait, isn't this like a problem?" He looked down at the letter again. "P.S. don't go out drinking all night just because I'm not home. That kid…"

This concludes the first chapter of the story. Thanks for reading.

This was a bit too long, folks, because Ben's transformation is what Ben 10 fans want to see the most in crossover fanfiction.

But here's some trivial information for this chapter. Nothing important, but left just as a note.

1) Benji Tenzaki is named to reflect Benjamin (Kirby) Tennyson. I included the kanji spelling but it didn't have any particular connection with the character's personality or powers. Ten () means heaven/ sky, which is probably the only part related to Benji's character.

2) Masato Tenzaki is also a play on Max Tennyson. But while being a mentor figure to Benji, Masato isn't his grandpa like Max is to Ben.

3) Like many other characters and people of Konohagakure, Benji also gained motivation from Naruto though he had a different approach to things.

4) Ben's backstory is inspired by Superman: Red Son. It has to wait to unfold…

5) Ben is sometimes characterized as someone with "Hero syndrome"/ hero complex by fans as he does hero work because he wants to be a hero and takes pride in it. However, he actually regretted it once people began to recognize him because he doesn't want fame, which is a somewhat exaggerated trait in my versions of Ben 10.

6) If I have to choose an opening song for this story, it'd be, Dilemma by Ecosystem, which is one of the many opening songs of Gintama.

If you want to know my opinions on the interaction between jutsu from the Naruto verse and Ben's Omnitrix, feel free to ask questions. This is it for now. Again, thanks for reading.

Chris Chronos.