User blog comment:Realmartialarts/Know your sources/@comment-5364175-20120920200810/@comment-4652104-20120923074801

Galactus? There is two ways to approach this.

One is to assume that we are talking about Earth and let it go. Galactus is a cosmic being and a force of nature, so there is no sense in getting him mixed up in this. How would you kill Death or Eternity? You wouldn't and that's it.

The alternative answer is: Infinity Gauntlet. It is in fact obtainable on Earth if you go about it the right way. With it you can basically kill anything and anyone.