Well, it could be really exciting. Ben 10 has all those cool alien forms he can transform into. Imagine him facing off against a Xenomorph. His Heatblast form might be able to use its firepower to keep the Xenomorph at bay. And his Four Arms form could have a physical fight with it. It would be a battle of different kinds of alien powers.
A Ben 10 and Xenomorph crossover fanfiction would likely involve some intense battles. Ben's alien devices, the Omnitrix, could malfunction due to the Xenomorph's strange biology. This would force Ben to rely on his wits more than his usual transformation powers. Maybe he'd have to team up with some of the characters from the Xenomorph universe to survive. It could also explore how the different species from both universes view each other.
Ben might initially be very cautious around the Xenomorphs. He's used to his own set of aliens, but these are something entirely different. He could try to communicate with them using his alien forms' unique abilities, but it might not work as the Xenomorphs are more about instinct. The Xenomorphs, on the other hand, would probably see Ben as a threat or a potential host.
In a 'ben 10 x fem xenomorph' fanfiction, the story could start with Ben 10 accidentally stumbling upon the fem xenomorph in a secret government lab. At first, they are hostile towards each other. But as the story progresses, they start to understand each other's motives. The fem xenomorph could be on a mission to find a new home for her species, and Ben 10, being the hero he is, decides to help her find a suitable uninhabited planet where her kind can thrive without causing harm to other species. This would involve a lot of adventure as they face various obstacles and enemies along the way.
It could be about Ben using his alien forms to fight alongside the Straw Hat Pirates in the One Piece world. Maybe he uses Heatblast to help Luffy against a fire - based enemy on a new island they discover.
Well, it could be really exciting. Picture Ben 10's aliens interacting with the mages of Fairy Tail. For example, Heatblast could have a cool battle with Natsu, comparing their fire - based powers. And the Omnitrix might be an object of great interest among the Fairy Tail guild members, who would be curious about its capabilities.
It could be really cool. Picture the powerful beings from Overlord in the world of Ben 10. Maybe Ainz Ooal Gown could use his magic against some of Ben's alien forms. The different power systems would create some interesting battles and interactions. For example, how would Ainz deal with an opponent like Four Arms? And how would Ben react to the undead hordes that Ainz commands? There are so many possibilities for epic crossovers in this fanfiction concept.
It could be amazing. Picture Ben with his Omnitrix facing off against the Teen Titans' villains. Maybe Ben would transform into Four Arms and have an epic battle with Cinderblock. The Teen Titans would be in awe of his powers and they could team up to fight a bigger threat like an alien invasion that threatens both their worlds.
In a Ben 10 Avengers crossover fanfiction, the story might involve Ben and the Avengers sharing their technology and knowledge. Maybe Iron Man could upgrade some of Ben's alien tech, while Ben could show the Avengers some unique alien abilities they've never seen before. It could also lead to some interesting character dynamics, like Spider - Man and Ben comparing their powers and how they use them to protect the city.
Well, in a crossover fanfiction, the Animorphs could team up with Ben 10. Maybe they'd face a common enemy that neither could defeat alone. For example, an alien race that has the ability to morph like the Animorphs and also has advanced technology like the villains Ben 10 faces. They could combine their powers and strategies. The Animorphs' knowledge of Earth animals and their morphing abilities along with Ben's various alien forms and his Omnitrix would make for some really cool battle scenes.
Well, one possible plot could be that Ben Tennyson and Naruto end up in the same dimension somehow. Ben could use his Omnitrix to transform into various aliens to fight alongside Naruto against a common enemy like a powerful ninja - alien hybrid villain. They would learn from each other's skills. Ben might learn about chakra control from Naruto, and Naruto could be amazed by the different powers of the aliens.
A Danny Phantom and Ben 10 crossover fanfiction would be full of action and adventure. The two characters have very different power sets. Danny has his unique ghost powers such as flight, invisibility, and ecto - blasts. Ben, on the other hand, can transform into a variety of aliens with different abilities like Four Arms' great strength or XLR8's super speed. In the fanfiction, they could be brought together by a common enemy that is threatening both the human world and the ghost zone. They would have to learn to work together, with Danny using his knowledge of the supernatural world and Ben using his combat experience from different alien forms. Their combined efforts would make for a thrilling story as they face challenges that neither could overcome alone.