Saitama would win. He has shown incredible strength with just one punch. His power seems limitless, and in a fanfiction scenario, his simplicity and raw power would likely overpower Jiren's more complex abilities.
One possible plot twist could be that Jiren discovers a way to nullify Saitama's strength. Maybe he finds some sort of energy - draining technique that weakens Saitama over time. Another could be that Saitama holds back for some reason, like he wants to see the full extent of Jiren's power, and in doing so, he gets into a real struggle.
In this fanfiction, Goku vs Jiren is likely to be an epic battle. Goku's power with the Universe's Watch might bring new and unexpected abilities. Jiren, on the other hand, is an extremely powerful opponent. The fight could involve intense energy blasts, high - speed combat, and strategic maneuvers. It might also explore the growth of Goku's character and his newfound power in relation to Jiren's unwavering strength.
Well, in this graphic novel, Deadpool's wacky and unpredictable nature clashes with Thanos' power - hungry and often brooding demeanor. It makes for some really interesting and comical battles.
In the fanfiction, the plot could develop such that the power of the universe's watch attracts other villains or powerful beings. They might try to steal the watch from Goku during his battle with Jiren. This would add a new layer of complexity as Goku has to fend off these new threats while still trying to defeat Jiren.
A possible plotline is that Thanos hears about the powerful chakra in the Naruto world and decides to conquer it. Naruto stands up to him, and during the fight, Naruto unlocks a new form of his power that is on par with Thanos' strength with the Infinity Stones. Along the way, Naruto teams up with some of his old foes who also realize the danger Thanos poses. They all fight together to protect their world.
The plot typically involves the Avengers facing off against Thanos. Thanos usually has some grand plan, like gathering the Infinity Stones to reshape the universe. The Avengers must come together, using their unique powers and teamwork, to stop him from achieving his malevolent goals.
One possible storyline could be that Thanos arrives on Earth seeking a powerful artifact. Superman steps in to stop him. They battle it out across the city, with Superman using his strength and speed to try and take down Thanos. Another could be that Thanos somehow manages to get Superman under his control using the Infinity Stones, and then the rest of the Justice League has to figure out how to free Superman and defeat Thanos.
A Harry Potter who reverses Thanos would be a very interesting concept. Harry could use his ability to communicate with snakes (Parseltongue) to perhaps take control of some of Thanos' minions. His magical items like the Invisibility Cloak would give him an advantage in stealth. He might even use the Time - Turner to go back in time and prevent Thanos from getting the Infinity Stones in the first place. The Hogwarts environment could also be a factor, with its many secrets and magical defenses that could be used against Thanos.