I'm not entirely sure about the exact plot details of 'ben 10 ultimate alien the big story'. It might involve Ben Tennyson using his various alien forms to face some big threats and challenges, but that's just a general guess.
Ben 10 Ultimate Alien is about Ben Tennyson who has the Omnitrix which allows him to transform into various alien forms. In this series, he has new challenges and enemies. He unlocks ultimate forms of his aliens, which are more powerful. He continues to protect the Earth and the universe from different threats.
In this story, the central character is Ben Tennyson. His ability to transform into ultimate aliens using the Omnitrix makes him the key figure. Gwen, his cousin, is an important part of the story too. Her magical abilities often come in handy during their adventures. Grandpa Max, with his wisdom and combat skills, is another mainstay. Additionally, there could be antagonists or supporting characters that interact with Ben, Gwen, and Grandpa Max. These could be other aliens, whether they are friends or foes, that add to the complexity of the story. For example, some of Ben's alien forms like Heatblast or Four Arms might have a more prominent role in certain parts of the story, depending on the situation and the challenges they face.
One idea could be a crossover where Ben Tennyson and Spider - Man team up to stop a common enemy like Doctor Octopus who has somehow gotten his hands on some of the Omnitrix's alien DNA. They could combine their powers and skills to outwit the villain.
Gwen would be a great character to pair with Alien X. Her magical abilities could complement Alien X's powers in interesting ways. For instance, when facing a threat that requires both brute omnipotent force and the finesse of magic. Another good pairing could be Kevin. His ability to absorb and use different forms of energy could interact with Alien X's power source in unexpected ways, like when they need to combine their powers to break through a powerful energy barrier.
Some of the alien characters themselves, like Heatblast or Four Arms, are also popular. Their unique physical characteristics and powers make them interesting to write about. For instance, Heatblast's ability to control fire can lead to all kinds of scenarios, from battling fire - based villains to using his heat to solve environmental problems in a story.
One common theme is friendship. The female alien often forms a strong bond with Ben, and they support each other through different situations. Another theme is power. The female alien usually has some unique power that plays an important role in the story.
One interesting story could be about an alien's unique adventure on Earth. Maybe it discovers a hidden power within itself while trying to adapt to human society.
It could be an alien bounty hunter. This bounty hunter has been hired to capture Ben in his stuck - as - alien form. The hunter might have some special gadgets or powers that make it difficult for Ben to escape. And he's not interested in Ben's well - being, just in getting the reward for bringing him in.
Power and responsibility is also a big theme. Ben has to handle the powers of his alien forms responsibly, especially when dealing with aliens. In many fanfics, there's also the theme of discovery. Ben discovers new things about the aliens, their cultures, and their abilities. For example, he might learn a new power from an alien that he can use in a different way. There's also the theme of cooperation, where Ben and the aliens work together to achieve a common goal, like saving a planet or stopping a powerful enemy.