One possible plot could be that Tornado initially challenges Saitama out of pride. She sees his nonchalant attitude and wants to prove that her psychic powers are superior. Saitama, being Saitama, just goes along with it. As the battle unfolds, Tornado throws everything she has at Saitama, but he just dodges casually. Eventually, Saitama throws a light punch that knocks Tornado back, but not seriously hurt, which makes her realize his true strength.
In a fanfiction scenario between Tornado and Saitama, Saitama would likely win. He's so overpowered that he can defeat any opponent with one punch. Tornado is extremely strong with her psychic powers, but Saitama's strength seems limitless. His simple training routine has made him so powerful that no enemy has been able to withstand his punch so far.
Another theme could be the clash of different universes. Amazo is from the DC universe and Saitama is from One Punch Man. Fanfics might play around with how these two different universes' rules and powers interact when these two characters meet. Also, there could be themes related to respect and rivalry. Saitama is often very nonchalant about his power, while Amazo is a complex android with various abilities. How they view each other in the fanfic can create interesting storylines.
The story of Megamind and Metro Man is quite interesting. Megamind, being the so - called 'bad guy', has a long - standing rivalry with Metro Man. Metro Man is the epitome of a hero, with great strength and the love of the people. Megamind, though smart, can't seem to get the upper hand. But when he does get rid of Metro Man, he finds that life isn't all that great. He starts to miss the competition. He then tries to create a new hero - like figure in Titan. But Titan doesn't quite turn out as planned. Megamind has to step up and re - evaluate his role. He ultimately becomes the hero the city needs, which is a big shift from his original villainous identity.
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.
One great Megamind and Metro Man fanfiction is 'The New Dynamic'. It explores what happens when Metro Man comes back after a long absence. The author does a wonderful job of portraying their complex relationship and how the city reacts to their reunion.
In a Saitama vs OC fanfiction, a plot twist could be that the OC has the power to make Saitama lose his strength. However, the OC doesn't want to use this power because they admire Saitama and want to test their own strength against him fairly. Another interesting twist could be that the OC is a part of a bigger plan by some mysterious organization. They use the fight against Saitama as a distraction while they carry out their real objective elsewhere. And as the fight progresses, Saitama realizes this and has to decide whether to continue the fight or go after the real threat.
Well, it really depends on how the OC (Original Character) is designed. If the OC has some really unique and powerful abilities that can counter Saitama's strength, like the ability to nullify physical attacks or something really out - of - the - box, then the OC might stand a chance. But Saitama is known for his one - punch knockout power. So, in most cases, Saitama would probably win due to his overwhelming strength that has defeated almost every foe he's faced so far.