User blog comment:Alanomaly/Epic Rap Battles: Aliens vs History - NEWS BLOG/@comment-4388002-20151110041717/@comment-5101200-20151110062535

In this case, "History" refers to anything non-Ben 10. However this also means no Generator Rex or Secret Saturdays as well due to crossovers. Machamp is Pokemon, therefore would go on the "History" side.

I think Rath vs Hulk would work better, due to the fact both get stronger the angrier they are.