One Punch Superman Saitama VS Tornado was the 191st chapter.
Chapter 191," Tornado's Counterattack ", tells the story of the battle between Saitama and Tornado. The two met on the street and Saitama was provoked by Tornado and was involved in the battle. In the battle, Tornado displayed her powerful strength. She used a type of Qigong wave called "Tornado" to attack her opponent, forcing Saitama to display even more strength to fight against her. In the end, Saitama defeated Tornado through his relentless efforts, demonstrating his unparalleled strength and tenacious will.
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.
Saitama's speed in the manga is incredibly fast. It's hard to put a specific number on it, but he can cover great distances in no time and react with lightning speed to any threat.
Saitama's strength in the manga is basically off the charts. He has no known limits and can take down any foe with ease. His power seems almost invincible.