@Mysterylobo Saitama does have at least 2 supernatural abilities/qualities, Invulnerability and One Punch Kill. Honestly I feel like he’s more fit to fight Superman then Batman
@Heartz13 Saitama claims he only strong cause of his " physical training" while genos guesses that Saitama doesn't know how he has or obtained these "abilities" at all. Even though Saitama have many feats showing superhuman abilities it not entirely explained my "logical" guess would be is that nappa son got transported to another world that affected him somehow to make him extremely weak and less saiyan like then many descendants later down the line Saitama was born and through his workouts he activate some resemblance of saiyan power without ki and loss his hair like his ancestor nappa but he so human and this universe would not allow him to be saiyan so it gave him superhuman abilities mysteriously .