One Punch Man is set in a universe where powerful superheroes with extraordinary powers are commonplace. While Saitama, the titular One Punch Man, is clearly the strongest hero by a wide margin, in both One Punch Man and anime in general, fans are split on whom the second strongest is—especially as there is a wide variety of characters to choose from, all with unique abilities that are tricky to compare directly. But, even in this crowded field, most fans give Blast the silver medal due to his seemingly immense strength.
Source：https://www.cbr.com/opm-blast-saitama-comparison/
