Galactus is a cosmic entity who devours planets; Spider-Man is a street-level hero with no path to victory.
This is one of the most extreme mismatches possible. Galactus is a cosmic entity who predates the current universe and consumes entire planets for sustenance. Spider-Man is a teenager with proportional spider strength who fights muggers and supervillains in New York City.
Spider-Man's intelligence is impressive โ Peter Parker is a genius who has outsmarted far more powerful opponents. But Galactus cannot be outsmarted by a lone street-level hero. The Power Cosmic operates on a scale that makes Spider-Man's webbing, punches, and spider-sense completely irrelevant.
In the comics, Spider-Man has stood up to cosmic threats through team efforts and cosmic power-ups, but on his own, he has zero tools that can even register against Galactus. This is not a fight โ it is a human confronting a hurricane.
Galactus is a cosmic entity who devours planets. His Power Cosmic can manipulate matter and energy at a molecular level. Spider-Man has literally nothing that can affect him in any way.
Spider-Man's genius intellect has found solutions to impossible problems before. His spider-sense might detect Galactus's attacks, and his courage means he would never stop trying to find a way to win.
Galactus wins without noticing Spider-Man exists. This is a cosmic entity versus a street-level hero โ the power gap is virtually infinite. Spider-Man's only option is to run.
Galactus also fights
Spider-Man also fights