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The Alien Hero of Teyvat

Chapter 1 - Arrival at Mondstadt

The world of Teyvat, and more particularly, the Mondstadt section of that realm. A breathtaking region that is characterized by trees that are full of life, waters that are peaceful, and air that allows you to experience a sense of freedom. At this very moment, though, a gateway has materialized out of thin air, and something that has emerged from it has just violently slammed into the ground.

"Ow." The mysterious figure stroked its head in apparent discomfort before a beeping noise started emanating from an insignia that was attached to its belt and began flashing. A sudden burst of light devoured it, and in its place stood a young man dressed in brown cargo pants, green and white shoes, and a white hooded jacket with green stripes on both sleeves. The number 10 was also colored green and was sewn onto the right side of the white jacket. The most intriguing aspect of this character is the alien watch that he wears on his hand.

It was none other than the legendary alien hero Ben Tennyson, bearer of the Omnitrix, who was seen here. After a battle he underestimated, he now finds himself in a place that doesn't seem to be Bellwood.

"Man. What did Psychobos do to me? That thing he used to attack me, he said, it would send me to another dimension. Have I been transported back to Rex's universe?" Ben cautiously stood up and did some light stretching in an effort to alleviate the agony in his hurting bones. Once he had gathered his wits, he looked around to figure out where he was.

"No way is this Rex's universe. So far, it looks too peaceful to have any freaky EVOs invading this land." This conclusion was reached by the alien hero after he observed the breathtaking scenery and took into account the fact that he was not in the midst of a city but rather in the middle of a forest.

Ben continued to stroll about in order to discover what else he could see besides trees and grass. Eventually, however, he did spy something out in the distance: a massive grey brick wall that looked like it had been copied directly out of a castle.

"Is that... a castle I spy on the horizon? To me, that screams "civilization"! Just pray this isn't a new faction of the Forever Knights." Tennyson began speeding toward the structure he'd seen in the hopes of learning more about the dimension he'd landed in.


At the gates of Mondstadt, the Knights of Favonius fought valiantly to thwart an attack orchestrated by the Hilichurl army. Because Acting Grandmaster Jean was participating alongside their Honorary Knight in the effort to solve the matter with Stormterror, the Hilichurls decided that now would be an excellent moment to launch their assault on the city.

The good news is that thanks to Outrider Amber's efforts and her scouting ability, they were able to prepare ahead and establish formations to fight off the army. The bad news is that more and more of them keep showing up. In addition, Captain Kaeya isn't around to lend a hand because he is "somewhere" else.

But despite this, the knights did not give up and continued to fight, exchanging blows with their foes. Amber was at the forefront of the attack, using pyro-arrows to take down a number of Hilichurls and reducing the shields of the Mitachurls.


"This place appears like it could be from the Middle Ages, which would explain my current predicament. NO! Which means Mr. Smoothy probably doesn't exist in this dimension." As Ben made his way towards the capital, he was complaining and becoming increasingly panicked while detailing the most significant drawbacks that this dimension had to offer.

Eventually he did make it, but he watched on with surprise as, the moment he arrived, he saw the raging battle between knights and beasts happening in front of him.

"Whoa, what the heck are those freaky creatures? Looks like they are planning a raid on the city, and the knights are doing their best to repel it." As Ben looked on, he noticed one of the knights in dire straits, on the verge of death. His heroism flamed up as he readied himself to enter the fight.

"It seems like they might use some help. Whatever the case may be, one thing remains constant throughout all dimensions. It's Hero Time!" Ben gave the Omnitrix a light tap, and its holographic user interface immediately illuminated. He kept scrolling a little farther until he located the correct alien. After he made his selection, the faceplate slid open, revealing the core, and he slammed it into place as soon as it appeared.


"More of the Hilichurls have been wiped out! Uh, why did Captain Kaeya leave all the dirty work here just to get drunk?" Amber let out a frustrated sigh as she thought about how lazy their leader was being. She promises to have a major rant for Kaeya if she ever runs into him again after the battle.

"Outrider Amber, Swan is hurt and in need of assistance!" Her attention was suddenly brought up when Huffman, one of the hardworking members of the Knights of Favonius, shouted out from behind her as he dealt with a few Hilichurls.

Amber turned her head to the other side, and regrettably, it was true. Swan has suffered an injury, and at this point, he is encircled by a swarm of Hilichurls that are planning to kill him.

She was going to run in and prepare to conjure a Pyro Shield to save Swan. But before she could, someone else rescued the knight and beat her to it. A giant brown fist connected with the army of Hilichurls, sending them scattering in all directions. But it wasn't a human being who did it; rather, a massive figure that no one recognized emerged in front of them, and its appearance caused her and the knights to feel a modicum of fear.


'So this is it, eh? Soon, I'll merge with the freely flowing wind and become one with it.' On the battlefield, Swan resigned himself to his fate. He battled valiantly and did everything in his power to ward off the assault launched by the Hilichurls and protect his city.

But then, at the last minute, it seemed the Anemo Archon deemed that it wasn't his time yet, as the Hilichurls surrounding him were swatted away. What he didn't anticipate, on the other hand, was for a savior to appear not in the guise of a person but in the form of a monstrous creature.

To be more specific, it was a dinosaur with some human characteristics, measuring around 12 feet in height and having hard skin that was brown on the outside and beige on the inside. Additionally, he sported a pair of black briefs with a white waistband and a green and black sash that bore the Omnitrix emblem across the center of his chest.

This was Humungosaur. An Omnitrix DNA sample from a Vaxasaurian. One of the aliens that Ben would call upon in the event that he required some extra strength and who excels at fending off large groups of adversaries.

"Are you alright?" The Vaxasaurian had a very deep, gravelly voice that genuinely frightened Huffman a bit.

"I-I'm fine." Swan stuttered out in fear as he was not expecting this creature to talk and just answered him

"Alright, go rejoin your pals. I'm going to deal with these guys in hockey masks right now." Humungousaur told Huffman to which he complied and immediately went back towards his comrades.

"Huffman are you okay?" Right away, Amber inquired about her teammate while she was checking on him.

"Just a few bumps and bruises, Outrider Amber. However, it appears that creature is here to provide assistance." Swan uttered these words in the midst of receiving medical care.

"What is it anyway?" Huffman asked aloud. A sentiment that was shared by everyone else as they made the decision to put the fight on pause and observe how things would play out in light of the recent turn of events.

Back at the battle, Humungousaur cracked his knuckles as he made his way slowly towards the army, who did not show the slightest sign of fear and instead screamed back at him.

"I think it's high time you all got some new masks. Because one, it's not working to mask your breath. I can smell halitosis coming all the way here. And number two, the massive beating I'm about to deliver is going to cause it to shatter." Running straight at the cluster of Hilichurls, Humungousaur slammed his massive body into the ground with devastating force. Those who were unlucky enough to be caught in the Vaxasaurian's path of destruction were flattened by his weight, and those who managed to dodge his blow were hurled far from the scene by the resulting shockwave.

The Hilichurls' doggedness shone through as they quickly returned to their feet and renewed their assault on Humungousaur, this time charging up close and slamming him with their clubs as the others covered a longer range with crossbows and rocks. Humungousaur, however, was unfazed by their blows and swatted them aside with his muscular arms and tail.

His forward momentum was abruptly halted as he was rammed and pushed back. Upon turning his head, he saw a Mitachurl attempting to knock him down by repeatedly striking him with a huge wooden shield. Despite the beast's best efforts, Humungousaur held his position and successfully blocked its charge.

"Smart of you to use a shield, too bad you're also dumb for using a wooden one." Humungousaur drew back his hand and smashed the shield so hard that it broke. The unexpected turn of events shook the Mitachurl to its core, giving Humungousaur a chance to land a series of powerful blows. The Mitachurl was eventually put out by a final blow from the Vaxasaurian.

The onslaught of Humungousaur was put to an end when he was abruptly struck by a bunch of ice shards along with some water, which resulted in his right foot becoming somewhat frozen as a result of the impact. He quickly broke through the ice by elevating his right foot and turning to face his new opponents, who were furious Cryo and Hydro Abyss Mages.

"I don't know who you are, but you should be on our side!" The Cryo Abyss Mage yelled at him and attempted to convince him to come and assist them.

"No thanks, I don't hang out with losers." Humungousaur waved off their invitation with a lack of interest.

"Then you'll succumb to your fate along with everyone else." The Hydro Abyss Mage let out a cry as he unleashed a volley of bubbles that were headed in the direction of the Vaxasaurian.

"Oh no. Bubbles. My very weakness." Humungousaur made a snarky remark that suggested he did not take the Hydro Abyss Mage's attack seriously. He soon realized his error when he touched it and found himself caught in a large water bubble, his air supply dwindling by the second.

"Hahaha! Who's the loser now, Geovishap?" While the Hydro Abyss Mage was making fun of Humungousaur, the Cryo Abyss Mage added insult to injury by moving about in front of him and dancing.

Annoyed with how the mages are acting, the colossal dinosaur slapped his chest, right above the Omnitrix emblem, and an emerald glow encompassed him instantly. It caused the Abyss Mages to temporarily hide their eyes, and when they reopened, they saw that the water bubble the Hydro Abyss Mage had created to confine Humungousaur was now steaming on the inside. The bubble eventually broke, revealing a brand-new, mysterious alien.

After the bubble burst, a life-form made of fire was seen emerging from it. High levels of heat were being emitted by the fire-based being. It was a Pyronite known as Heatblast, whose temperatures can surpass those of a supernova.

"Huh. I was planning to use Big Chill, but Heatblast will have to do." The Pyronite's grip on his hands grew tighter as he fixed them with increasing resolve.

"What just happened?!" Swan yelled out in disbelief as he witnessed the Geovishap transform into a Pyro Vision that resembled a human being. It turned out that he wasn't the only one to have that reaction; Amber and the other knights did as well, and all of them became even more wary when they considered the possibility of a shapeshifter.

"What the?! Where did that naked, Geovishap-like creature go? And who are you?!" The mages, just like the knights, were taken aback by the sudden appearance of the otherworldly being in front of them.

"The name's Heatblast. Water-boy. Now why don't you and your friend Ice Brain get yourselves a nice tan." In an instant, Heatblast unleashed a raging blaze that swept towards the two mages. As soon as the fire touched the elemental shields, the ice mage's barrier melted and the water mage's shield evaporated, rendering them powerless against the onslaught.

"Gah!" The mages collapsed to the floor, writhing in pain from the burns inflicted by the ferocious flame attack. They were so weak and lightheaded that they could hardly stand. When they were able to get to their feet, they saw Heatblast coming at them with a menacing look on his face.

"Unless you punks want a permanent sunburn, I suggest you all scram." Heatblast gave them one last stern warning. With reluctance, the Abyss Mages came to the conclusion that a strategic retreat was necessary, and so they followed the rest of the Hilichurls as they ran away.

Heatblast, content with the outcome of the battle, turned back to see how the Knights of Favonius were doing. All of them, as he had predicted, were completely taken aback by the unexpected turn of events. Nonetheless, the knights remained wary as he approached because he was a strange creature they had never encountered before.

"H-halt! We don't know who you are or why you're here, but we won't let you burn Mondstadt to the ground." Amber drew her bow and remained standing, prepared to fight against this creature. While she was normally helpful to strangers, she felt on edge despite his assistance.

"Woah, no need to be on guard. I'm a good guy, and I mean you no harm. I bet you've never seen a Pyronite before." Heatblast raises his hands in an attempt to show he isn't going to do anything shady.

"Pyronite? Wait, can creatures be blessed with Visions now?" Amber slowly lowered her guard after hearing what the creature had to say to them. Despite this, she along with the knights was still uncertain about what a Pyronite is.

"I'll take that as a no. But don't worry, I'm like the rest of you guys." Heatblast slams the Omnitrix emblem into his chest, bathing him in a green light that causes the knights to shield their eyes. Once the light standing in for Heatblast had gone out, Ben Tennyson had reappeared.

"Hey there I'm Ben Tennyson." Smiling confidently, the hero from another dimension introduced himself to the other knights.

Just like that, the Knights of Favonius and Outrider Amber's brain finally broke. First, some creature that looked like a Geovishap appears and saves them, then it changes into a giant walking Pyro Vision, and finally it changes into an ordinary human boy. May the Anemo God hopefully bless them with the extra brain power to process all this.


Author's Note

This is my first ever fanfiction posted here. I'll be honest; I'm not sure how frequently I'll post due to being busy. I just wanted to post it as a potential drive for a Ben 10/Genshin crossover since it lacks it here on the website. I'll see if I can post more, but if anyone wants to use this story as a base and write their own version, be my guest.