V-r0cK on 19 July 2015
Superman is weak outside of Earth (He'd be just like a human back on Krypton)
Goku strength is consistent everywhere, he can just teleport Superman to an atmosphere where it'll strip Superman of all his powers and Goku can just toy with him as if Superman is like Mr. Satan. Goku could also just destroy the sun making Superman weak as well.
Superman has enough weaknesses that Goku can exploit if he wanted to.I don't get how this was ever a challenge for Goku.
