The act of two men sitting or standing side by side, and extending their hand towards their partner'spenis and jacking off creating the "X" from the intersections of the arms.
{First off, I sometimes wonder if this Urban Dictionary was created as some kind of breeding ground for idiocy...
In the Marvel Universe, A particular group of Mutants (Homo Superior as opposed to Homo Sapien) with special abilities who have grouped together to defend humanity as well as they can. Although a significant portion of humans hates mutants, they still strive forward to show mutants are not all evil as many think.