Author Notes: Hey, you guys welcomed back for a brand-new story. Here's a Ben 10 and Black Clover crossover. I hope you guys would like and enjoyed it.

I've had read other Ben 10 and Black Clover crossovers, so I've decided to do one on my own.

Disclaimer: I don't own Ben 10 or Black Clover they belonged to Cartoon Network and Shonen Jump.

Don't forget to fave, follow, and leave your reviews.

Enjoyed!


Chapter 1: Brand Magic World

Bellwood...

On the streets of Bellwood two teenage boys are driving in an orange and white truck with an old man in a red shirt.

The first one was a Revoonahgander. He was tall, with periwinkle-blue colored fur, black marking on his face, and pointed ears. The middle of his face was white. He carries the white and black, gun-like device on his shoulder called the Proto-Tool and wears very durable blue and black Proto-Tech Armor.

His name was Rook Blonko.

The second boy was around 16-year-old with brown hair and green eyes. He was wearing a green jacket with white stripes and number 10 on it, along blue jeans and black and white tennis shoes. On his left wrist is a green, black, and white wristwatch-like device with a green and black hourglass symbol.

This was Benjamin 'Ben' Tennyson... wielder of the Omnitrix.

From a young age, Ben had always wanted to be a hero, growing up he tried time and time again to protect those who were treated unfairly, but because of his small size he was never successful.

At the age of 10, during his summer vacation, Ben went on a cross country, camping trip with his grandfather, Max Tennyson and his cousin Gwen Tennyson. Ben thought it was going to be an average summer hanging out with his grandfather and constantly fighting with his cousin. That is, until his first night out camping when he came across a piece of highly advanced alien technology called the Omnitrix; an alien wristwatch deiced that has attached itself to his left wrist, allowing him to modify his DNA, transforming him into various extraterrestrial superheroes.

From thar day forward Ben was thrust into an entire universe full of heroes, villains, magic, technology, aliens, and even old gods. And Ben loved every moment of it; he was finally able to be the hero he wanted to be. Over the last 6 years, Ben has grown in maturity and powerful, defeating many tyrants and overlords and sometimes just the run-of the mill bad guys.

Yet that hasn't been the case in the last few months for Ben. Things have changed quite a bit, after defeating Maltraunt and stopped him from altering the beginning of the universe by using an Annihilarrg that would be destroying the current universe and made a new one in his own image, which he would rule, and he thought that Ben has been killed. But Ben survived thanks to the Omnitrix's fall-safe would protect him from dying; something which he'd always guessed it had. Ben transformed into Feedback and absorbed the Big Bang and blasts Maltruant with the Annihilarrgh's energy, causing the rogue Chronosapien to implode into bits and pieces. After he was defeated, the Contuemila invited Ben and Rook to watch their universe be created. Then the Contuemia invites Skurd the Slime-Biost to join his ancestors, Skurd shares a heartfelt goodbye with ben willing detaching himself, joining the other Slime-Biolts to send DNA throughout the created universe.

Professor Paradox arrives, praising Ben for not letting him down, he informed Maltruant is stuck in a time loop. The Time Walker invites Ben and Rook to help him hide Maltraunt's parts across the multiverse before sending them home. While Ben and Rook have another day at Mr. Smoothies, although Ben was bored; having witnessed the creation of a universe with his days. Ben declares that him, Rook, Gwen, and Rook to go on a road trip across the universe. While on the road trip Azmuth gave Ben the evolutionary feature back to keep the Omnitrix from the falling in the wrong hands.

Right now, Ben and Rook are driving to Fredkin University to visit Gwen, Kevin, and Zed.

''How nice is the field air when we go to visit Gwen's college.'' said Rook.

''Yeah, I know, this field air nice.'' muttered Ben with listless and bored.

''What's wrong Ben?'' asked Rook. ''You don't look lively for the visit.''

''It's not that Rook, of course I'm happy to visit Gwen, Kevin, and Zed, it's just that I feel so bored these last days...'' explained Ben.

''Are you still waiting for an event that threatens the universe so you can fight and save it for umpteenth time?'' guessed Rook.

''How did you guess?'' asked Ben in disbelief.

''I just assume.'' answered Rook.

''Really?'' asked Ben. ''Well, you nailed it...''

''Hmmm. I imagined.'' replied Rook.

''That thing is, I'm glad no huge chaos breaks out in the city or in the universe, but I don't know, all the same tie I wish something had happened that we have to solve, help or save.'' explained Ben.

''I feel you Ben, sometimes I want to go there, find an evildoer or kick butt, but we also have to appreciate these moments of peace that we have because this is the result of our excellent as Plumbers.'' admitted Rook.

'''Yeah... you're right, but I'd still like something... interesting to happened, something to take away this boredom.'' stated Ben.

''Look Ben, we're almost there.'' Rook points to the University's Welcome sign.''

Unknown to Ben and Rook a hooded figure was wandering around the place, until they saw the Proto-Truk pass by, and they smirked at him.


Fredkin University...

Ben and Rook arrived at the university campus and found a girl with long orange hair, blue sweater and black stockings.

This is Gwen Tennyson, Ben's cousin.

A muscular young man with black hair, brown eyes with a black shirt with grey sleeves, blue pants and black shoes.

This is Kevin Levin.

Next to Kevin was a blue dinosaur like dog.

This is Zed.

''Hey, guys.'' greeted Gwen. ''We've been waiting for you.''

''What's new?'' asked Kevin. ''Tennyson and Rook?''

Zed barks cheerful.

''Hello, Ms. Tennyson and Kevin.'' greeted Rook.

''Hey Gwen.' greeted Ben. He turned to Kevin. ''Kevin Levin.'' he bumps his fist. ''How's the workshop going?'' he asked.

''It's all good, I have everything under control, a lot of work in car repairs consumes a lot, that's why I always wait for the end of the semester, because at least I have an excuse to have a short but effective vacation.' explained Kevin.

''For that excuse, you have a lot of orders pilling up.'' remarked Gwen.

''Tch... whatever, hey Rook, would like to help me with some orders?'' Kevin asked Rook.

''Hmm, it wouldn't hurt to have a hobby while I'm at college, so yeah, I'll help you out with some orders.'' answered Rook.

''Thanks man, you know sometimes I think I need help.'' replied Kevin.

''And why don't you hire employees?'' asked Rook.

''And share my profits, no thanks.'' admitted Kevin.

Rook and Kevin head to the workshop with Zed.

''What are you going to do Ben?'' Gwen asked her cousin.

''I don't know, maybe I'll walk around the university or order a hamburger at the food truck, I feel bored since I've gone days without doing something heroic.'' answered Ben.

''Come Ben, you can do a lot of things here, like go the library, go to one of Professor Hex's end of semester supplemental classes and... and...'' began Gwen.

She looked at him and sees him with a disappointed look on his face.

''Well considering the way you look at things, there aren't many interesting things you can do here.'' she continued.

''I see, well never mind, I'll see what I can entertain myself with in this place, good luck with your supplementary classes with Professor Hex.'' said Ben.

Ben walks away.

''Thanks, hey how did you know what...?'' asked Gwen.

After the chat that the cousins had, they didn't they were watched.


The library...

Ben decided to go for a walk in the university facilities and then go to the library with the minimal hope of finding a comic book of Sumo Slammers while consuming a hamburger that he bought from the food truck.

What Ben didn't know was he was being followed and very quietly, it was none other than the hooded guy. When Ben arrived at the library, he began his search for any magazine or comic book of Sumo Slammers, to his bad luck, he spent 2 hours and found nothing in the huge library.

Ben decided not to transform himself into XLR8 or Fasttrack to avoid such a simple search. Ben: defeated.

''Damn, well, I saw that coming.'' he muttered. It was obvious that he wouldn't find anything interesting.

Suddenly Ben dropped a couple of books on his head and saw that on the 2nd floor was the hooded guy with two books in his hands, which apparently were the one he was looking for.

''Hey, who's there, I'm talking to you!'' yelled Ben.

Ben went to chase the hooded guy, while he was trying to run away from his purser.

Both were running down on of the corridors, Ben was activating the Omnitrix, but Ben was blasted by an attack of dark energy causing him to crash into a wall.

''Ouch that really hurt. Who is that guy?'' he wondered.

Ben gets up and continued the chase.

Meanwhile, the hooded subject continued to run with the aim of losing Ben, until he turned and came face Ben who had transformed.

Ben had transformed into a humanoid frog-like alien with three fingered hands and two-toed feet. He is, however, considerably taller, more muscular and paler skinned than a typical Incursean and ha a more defined jawline. He wears green sunglasses, a black bodysuit with a green stripe down the middle, fingerless black gloves, toeless black boots with green cuffs above them, and a green belt with a white buckle. He wears the Omnitrix symbol on his upper chest.

This was Bullfrag, Ben's Incursean form.

''Hello.'' grinned Bullfrag in a light Brooklyn accent. He kicks him, sending him through a couple of walls and into a tree on campus.

When Ben arrived on campus, he was greeted by several projectiles of dark energy.

Bullfrag dodged them with his jumping ability, but he managed to dodge them and went straight at the guy to punch him, but the guy was also dodging the punches.

Until one of Bullfrag's fists hit him in the head, making his helmet fly off and the hood tear, and then he could see who the guy was. The inucrsean's eyes widen in shock.

''Darkstar?!'' he asked in shock.

The person in front of him was indeed Michael Morningstar also known as Darkstar. When the Highbreed started invading Earth. Max Ben and Gwen's grandfather had left Ben holo-message about recruiting Plumber Kids Michael was one of them with ability to manipulate energy. After Ben, Gwen, Kevin, and Michael fought a group of zombified schoolgirls from unknown origin, Kevin guessed that Michael was the one responsible for those zombification's. His guess later proved to be tight when Michael drained Gwen's energy and becoming nearly unstoppable an easily defeated both Ben and Kevin. However, Gwen proved to have enough will to resist his control. and drained her energy back from him, as well as part of his own, leaving him weakened. His other zombie victims then turned against him, and took back what remained of his energy, leaving almost desiccated and powerless. His Plumber badge was then taken and destroyed by Kevin, who stated that he doesn't deserve it.

But over the weeks his powers had gradually returned much stronger and more powerful than before since that day he became Darkstar. In order to get revenge, he tries to get, Ben, Gwen, and Kevin arrested by Magister Prior Gilhil for impersonating Plumbers and by making a deal with a Highbreed lord he defeated. When the Highbreed did his part of the deal, Darkstar tried to Ben, Gwen, Kevin, the Highbreed, and Gilhil's life force energy, but he was unable to absorb Gwen's because she escaped. He later captured the four and was about to absorb all of their life force energy when Gwen came in within the DNAliens in which he was unbale to absorb all of them because of fatigue. He was defeated by Be using a combination of his aliens. Afterwards, he was arrested by Magister Gihil and thrown in the Null Void.

Darkstar is eventually released from the Null Void by Cooper so he could help them stop the Highbreed Invasion. After the fight was over, Darkstar managed to evade them. After that Ben and his team had many encounters with Darkstar since then.

''What are doing here, and what you those books for?'' demanded Bullfrag.

''Ben Tennyson, it's a surprise to find you here and even more so in a library.'' commented Darkstar.

''Forget your villain monologue and answer my questions or would you rather I kick your butt like the other times?'' asked Bullfrag.

''Haha.'' laughed Darkstar. ''With the confidence of always Tennyson, I'll just tell you that what I plan to do is beyond your understanding.'' he shoots another dark beam directed at the alien hero.

Bullfrag dodged it, but the beam hits a statue in the courtyard causing an explosion.


The explosion had a huge impact that caught the attention, Gwen, Kevin, and Rook, causing the three of them to stop what they were doing and head for the site of the explosion.


Bullfrag was still dodging the attack from the statue. He kept dodging Darkstar's attacks until he got tried or until Gwen, Kevin and Rook arrived.

''Say still Tennyson!'' shouted Darkstar as he keeps shooting at him.

''Yeah right, I'm not going to let myself get sot, it's finally happening, something I've been missing doing for the past few days and that's kicking but!'' Bullfrag shouted back.

With his enemy keeps shoot energy beams Ben had to charge into another form to counter them he knew the right one.

Bullfrag slapped the Omnitrix symbol causing his body engulfed in a flash of green light.

When the green light died down standing in his place was a humanoid silicon-based alien made of extremely durable crystal. His body is overall indigo, with several dark lines and spots. His hands and face are magenta, and he also sports six magenta shards on his back, two on his chests, and one top of his head that resembles a horn. His face consists of a mouth and one large green eye at the center. He wears the Omnitrix symbol on his chest.

''Chromastone!'' he shouted.

Chromastone held up his hands and absorbed Darkstar's beams. His body engulfed in colors of the rainbow.

Chromastone fired a large ultraviolet beam at Darkstar who dodged it.

Both Chromastone and Darkstar continued to battle, until Ben's team arrives.

''Darkstar!'' shouted Gwen, Kevin, and Rook.

''What are you doing here?'' asked Gwen.

''Loverly Gwen, I'm just on a collection trip, I just need a few more items from here and I'll be ready to start my plan.'' explained Darkstar.

''Yeah right, like I'm going to let you do that!'' yelled Chromastone.

'I'd love to stay around, but I've got a pickup to make, so I'll see you around. Polvius Exitus!'' provoking a wall of smoke.

Behind that wall of smoke Darkstar disappeared from the eyes of Ben and his team.

When the smoke was cleared Darkstar was gone.

''Dang it, he's got away.'' groaned Kevin.

In a flash of green light Chromastone transformed back to Ben.

''He couldn't gotten have gone far.'' stated Ben.

''Miss Tennyson, can you detect his presence by his mana?'' inquired Rook.

In response Gwen began sensing Darkstar's mana. Until she finally got something.

''He's inside the building and he's collecting a few items that he like said would.'' informed Gwen.

''Where he is now?'' asked Kevin.

Gwen sense Darkstar's mana ad she picked up something.

''He's back to the library and it's looks like he's about to do a spell.'' answered Gwen.

''Whatever is he's doing. We can't let get him away.'' concluded Ben.

''Agreed, we've got to stop him.'' said Rook in agreement.

''You're right, whatever book he took is not good.'' replied Gwen.

''So, what are waiting?'' asked Kevin. ''Let's go!''

With that the group ran off towards the library.


The library...

At the library after collecting the items he needed, Darkstar drew some chalk lines on the floor to form a hexagram while lightning some candies at each end of the hexagram to prepare to prepare the spell that he was about to perform. The book he had stolen was a grimoire that was black with stars and portals on it.

Darkstar looked at the grimoire. He smirked through his helmet.

''With the Trans-Dimensional Grimoire, I can travel many universes that have magic, and I will be unstoppable, and I'll take over this world and another one.'' chuckled Darkstar evilly.

''I don't think so!'' yelled a familiar voice.

Darkstar turned around to Ben, Gwen, Kevin, and Rook who had arrived in just to stop the villain.

''So, that book you stolen is called the Trans-Dimensional Grimoire?'' asked Ben.

''Yes. It comes from another universe. And it has been in ours ever since.'' explained Darkstar. ''With it I can travel to other universes.''

''Well, you're not getting with it.'' Gwen told him.

''Yeah.'' agreed Kevin.

''Surrender now, by the order of the Plumbers!'' warmed Rook.

''Never!'' yelled Darkstar he fired dark energy beams at them.

Ben activated the Omnitrix scrolling through the holo-playlist and selected an icon head and slammed the dial down causing his body engulfed in a flash of green light.

When the green light died standing in Ben's place was a phantom/ghost-like alien with a gaseous appearance and claw-like hands, and white skin with black lines running all over him. His skin is removable with black and white striped tentacles underneath it. He has a green eye with a black pupil. He wears the Omnitrix symbol on his chest.

''Ghostfreak!'' he shouted in a whisper faint voice.

Darkstat would fire dark energy beams at Ghostfreak as Ghostfreak would turn intangible, thus causing the blasts phased right through him. Ghostfreak punched the villain in the head sending him back.

Gwen threw pink energy discs at him. Rook shoot laser blasts from his Proto-Tool.

Kevin absorbs the material from the floor and prepares to attack Darkstar..

Darkstair would counterattack Gwen and Rook's attacks and dodged Kevin's blows, and in one swift move, Darkstar sends Kevin flying to where Gwen and Rook were, knocking them down in the process.

''You know, I'd love to keep fighting you guys, but I've got everything I need, so I'll take my leave now.'' Darkstar.

Darkstar opened the grimoire, and he began reading it.

''Interdimensional...'' a fist would hit Darkstar from behind causing him to fall on down on the floor.

He turned around to Ghostfreak the one who punched him. Then Gwen, Kevin, and Rook stand back on their feet.

''I'm afraid not, Michael.'' said Ghostfreak.

''You fools! Do have any idea what you've done?!'' asked a distressed Darkstar as he turned to face them.

''Yeah, we do, stopping you.'' answered Kevin with a smirk.

''You have disrupted the cross-dimensional spell, creating a vacuum across space-time in the process.'' explained Darkstar.

''And that's bad because?'' asked Ghostfreak.

''Because everything and everyone within a mile radius will be sucked into the portal, sending them to anywhere across universes.'' explained Gwen.

''What portal?'' asked Ghostrfreak.

As if to answer his question, a large blue portal would suddenly materialize above all of them on the celling of the library.

''That one.'' stated Gwen dryly.

Like a vacuum, the portal would begin to suck in anything and everything inside library, causing all its residents to employ different means in order to avoid being sucked in as well. Kevin placed his right hand on the ground, causing his body to coat in the material of the ground. He would when enlarge before digging them deep into the ground, his impressive grip strength preventing him from being thrown into the air.

Rook would fire a grappling hook from his Proto-Tool towards a faraway bookshelf. The strength of the hook and line would prove to be sufficient enough for Rook to resist the portal's pull.

Gwen on the other hand would have to resort to more desperate measures, holding onto the top of a bookshelf with one hand, and holding firmly one hand of Ghostfreak.

''How do we stop?!'' asked Kevin due to growing desperation of their situation and the wind blowing violently as a result.

''We'd have to get to grimoire, and we can reverse the spell, but we can't reach it on time because we're gonna suck into the portal.'' responded Gwen.

''Point taken!'' shouted Rook.

''Any other ideas?!'' asked Ghostfreak.

''If we can send the caster of the spell through the portal, that should be enough to close it!'' suggested Gwen.

Darkstat's eyes would then widen in shock via his helmet as he came to, the haunting realization of what Gwen was implying.

''You wouldn't!'' yelled Darkstar, causing Gwen to smirk and Ghostfreak to narrow his eye.

''She would!'' called out Ghostfreak smugly. He placed his hand by the Omnitrix symbol. ''And. So. Would I!''

Ghostfreak slapped the Omnitrix symbol and transformed into a different alien in a flash of green light a humanoid alien with turquoise/light green colored skin, long toe-less legs with protruding kneecaps, arms that ended in barrels with bright, glowing green energy with a white center in it and three fingers with sharp, black fingernails that bent inwards in the middle. His head was adorned with a mask-like covering with three spikes growing from the top make it look like a crown. The mask covered his whole face expert for his mouth and green, pupil-less eyes. His shoulders had two black, circular disk and his back had two turquoise fins like that of a shark. He wore a white shirt with a black stripe in the middle and black pants that had three white circles adorning them one just below the knees, one on the soles of his feet and one between them. He wears the Omnitrix symbol on his left shoulder.

''Gateway!'' he shouted.

Darkstar fires a powerful dark energy blast, the blast was heading towards the Vortix Hawkian.

Gateway grinned and held out his left hand. Suddenly, a green nebula-like portal came into existence in front of him and absorbed the blast. The portal disappeared and another one appeared in front of Darkstar as his own attack flew out and hit him in the chest.

''Ahhh!'' cried Darkstar in pain as the attack blew him towards the portal.

In an act of desperation fired a large energy blast towards Gateway. Before he could do anything, he was hit by the blast.

''Oh, no!'' shouted Gateway as he was hit by the blast. ''Woahhh Gateway was levitated off the ground towards Darkstar.

''Ben!'' cried Gwen, Kevin and Rook in unison as they watched both of them be sucked into the portal.

At that moment, the portal would briefly expand, slightly sucking in more objects and raising Gwen, Kevin and Rook up to the air, before disappearing just as fast, causing them and the remaining objects inside the library to fall to the ground with a heavy thud.

''Uggh.'' groaned Gwen, Kevin and Rook as they slowly got off the ground.

''The portal's gone...'' said Kevin as he stood up.

Indee, the crisis had been averted, but a heavy price.

''... And so is Ben...'' muttered Gwen somberly as she knelt on the ground with a downcast expression.

''Gwendolyn. Do you have any idea where he might have gone?'' asked Rook as he knelt in front of her and Kevin.

''The book that Darkstar had was a multiversal-traveling grimoire, Rook. Meaning he could any universe, or in a whole new realty.'' explained Gwen. ''And I wouldn't even know where to look.'' she had sorrow in her eyes.

''And the worst part is Ben is somewhere with Darkstar.'' stated Kevin.

''Perhaps should we ask Professor Paradox?'' suggested Rook. ''He has knowledge of the multiverse. He might know where the portal sent Ben.''

''Hmmmmmm... Not yet, find's out find out what items Darkstar had stolen first so he can find out what's he planning.'' confirmed Gwen.

''I guess you're right.'' agreed Kevin.

'' To be honest with you that's a good option before asking Professor Paradox, and we shall investigate the items that Darkstar had stolen, and we'll find Ben no matter which dimension he's in.'' declared Rook.

So, the team set out to prepare their investigation of Darkstar's plan is. Gwen looked at the sky worrying about her cousin.

''Ben, wherever you are. We will find you.'' she whispered. ''Stay safe out there.''


Somewhere else...

''Ahhh!'' screamed the voice of Gateway in unison as he fell through the portal from above before lading with heavy thud and grunt of pain on the ground.

Gateway stands back on his feet.

In a flash of green light Gateway transformed back to Ben in a flash of green light.

''Gomma fell that tomorrow.'' groaned Ben as he sat up and began to run his head lightly. Ben began to stand up and began to observe his surroundings. ''Where I am?''

The setting was a forest.

''I don't think I'm on Earth or not. My Earth, at least.'' mused Ben. ''Meaning Darkstar did actually send me to another universe. But where is Darkstar. The portal must send him so that means he could anywhere by now.''

Ben decided walked through the forest to find a city or town. However, his searching was over. But by the near of the forest. He saw a village head up.

''A village, huh?'' Ben asked himself. ''Hopefully, I run into some friendly locals in the village, I might be lucky to run anyone, really nice.'' said Ben with a smirk.

Ben begins walking towards the village. While walking Ben would think about of a certain villain.

''Everywhere you are Darkstar. I'm going to find you and I'm gonna make you send me home.'' thought Ben.


A/N: Well, that is for the first chapter of my brand-new Ben 10 and Black Clover crossover readers. I hoped you guys like and enjoyed it.

Now for some things you should know about the story.

Ben gets to send to another universe with one of his enemies. And in my other Ben 10 crossovers get sends to another universe by his enemies.

And for Black Clover this set during episode 3 before Asta and Yuno leaves for the Royal Captial.

Anyway, Ben is now in the world of Black Clover, and he had to find Darkstar and stopped whatever he's planning to do.

I've read other crossovers where Ben gets to another universe along with his enemies so, I had decided to do one too.

In the next will have Ben going to Hage Village. What's going to happen?

Anyway, that is for now. See you guys in the next chapter bye for now.