User blog comment:DudeWithASuit/Bobdave vs Mr. Potato Head. Dwassy G's Underground Rap Battles/@comment-25061673-20150131085047

Off the top of my head, here are some suggestions

Tiger vs Tigger

Bantha vs that monkey from Friends

GIR vs Invader Zim

Legion vs Some X-Men person

Baby GG vs the Gerber baby

Wachowman vs Macho Man

Piet vs Walter White/Sheldon Cooper

I'll update this if I think of anymore. Great battle DWAS. :)