It's possible that the man who beat Pac-Man had a unique approach, combined with luck and determination. Maybe he discovered some hidden tricks or glitches in the game that gave him an edge.
Batman won against Superman because he was able to think several steps ahead. He anticipated Superman's moves and had the right tools and tactics ready. Plus, he knew how to play on Superman's moral code and emotions to throw him off balance.
Batman usually outsmarts Superman. He uses his intelligence and preparation to exploit Superman's weaknesses, like kryptonite or finding ways to neutralize his powers.
In comic vine, it's a tough call. Superman is incredibly powerful, but Batman is known for his intelligence and preparedness. It could go either way depending on the circumstances and the writer's imagination.
One possible scenario in Batman and One Punch Man fanfiction could be a battle of wits between Batman and Saitama. Batman, with his strategic mind, would be intrigued by Saitama's overwhelming strength. Saitama, on the other hand, might be confused by Batman's complex gadgets and plans.
A fanfiction could show Saitama getting lost in Gotham. Batman finds him and is immediately on guard because of Saitama's strange appearance. But when Saitama just asks for directions in his usual bland way, Batman is a bit taken aback.