One Punch Man Chapter 170 has established that the “greatest prophecy” is yet to occur. The battle against Cosmic Garou itself had gone to planetary levels as Saitama and the Hero Hunter fought on one of Jupiter’s moons.
The battle left the moon completely obliterated as Saitama was finally able to fight someone seriously. During this fight, we saw Saitama’s strength gradually increase, even causing one of his sneezes to pass through the moon and expose Jupiter’s core. This strength displayed by Saitama caused Garou to fear Saitama and resort to throwing him towards the Sun. Unfortunately for him, Saitama survived.
If a battle that was fought on a planetary level wasn’t the prophesied catastrophe, Saitama’s next battle could be something really big.
What is the Greatest Prophecy in One Punch Man?
In One Punch Man chapter 28, we saw Shibabawa foresee a violent future that would destroy the Earth. Looking at the fight between Saitama and Garou, the readers must have presumed that the prophecy had finally come true. However, according to the latest manga chapter, that is not the case.
In One Punch Man Chapter 170, we see Sitch and Sekingar in the Hero Association Headquarters. Here, they discuss Silver Fang’s retirement as he has told the association that he will train and rehabilitate Garou to take his place in the organization.
Considering Garou’s actions, it seems to be a huge risk for the organization to bring him into the organization. For instance, there could be a major backlash from all the heroes and citizens involved in the incident.
However, they do not have much of a choice as Silver Fang’s retirement would leave a huge hole in the Hero Association. They must also do all that they can to bolster their forces in preparation for the Great Prophecy.
Back in One Punch Man Chapter 28, Shibabawa herself wasn’t able to describe the catastrophe much, owing to her death due to choking on cough syrup. But according to the latest chapter, the Hero Association might just know more than we thought about the prophecy.
What could be One Punch Man's next big catastrophe?
One Punch Man’s next big catastrophe has to be something really big, considering that it must surpass the levels displayed in the fight between Saitama and Garou. Moreover, their fight was absurd as it left humans dead due to Garou’s cosmic radiation.
Along with this, the fight took place across the Solar System, all the way from Jupiter to the Sun. We witnessed Saitama flipping a moon’s surface by using only one of his arms. He used serious punches, omnidirectional serious punches, and even destroyed a moon with his sneeze.
It hardly seems possible that even if a catastrophe were to arrive, it could take down Saitama. He has infinite strength and speed, so someone being stronger than him would simply ruin the story, unless the mangaka pulls out an amazing plot (maybe involving the God).
The only way there could possibly be an Earth-destroying catastrophe is if Saitama stops being a hero. Otherwise, it could also be the case that the manga shows us a gag situation where Saitama simply couldn’t fight as he was busy, during which the Earth gets destroyed, causing him to go back in time, just like at the end of the fight against Garou.
Or maybe the catastrophe had already arrived in the form of Boros or Garou, but Saitama is so "broken" that the prophecy doesn’t account for him. Even so, Sitch and Sekingar believe that the Great Prophecy is yet to occur, so only time will tell what it will be.