Because of spider-man's intelligence, experience and skills but obviously his superhuman physical stats work too, he got good base, but here's the thing, thanks to his spider-sense and agility he capable of defeating anyone in 1v1, of course superman, hulk or spawn can beat spider-man, but I'm talking about superhero teams, any version, and he got experience, he beated the avengers and hulk before. It just the overpowered heroes would catch him off guard and beat him instanly. In 1v1 Batman vs Spider-man, if batman isn't prepared, spider-man got the advantage

Spider-Man beat the Avengers when they were mind controlled and not thinking straight.

How strong was the multiverse vampire Morlun anyway, just curious?

I disagree.

beyonder spider-man wins!