[Darth Vader]

I know, they're just all so funny and amazingly done, and the people who actually portray the characters really get into it, which I love. The one guy who portrays Chuck Norris in the Abe vs. Chuck battle has the funniest facial expressions in the second half of his rap. xDD

Personally, I think Obama won in Obama vs. Romney, it's hard to say for Einstein vs. Hawking, but I think Hawking pwned a little bit more, Chuck Norris butchered Abe at the end, Mr. Rogers beat Mr. T by a long shot, and Hitler had some epic rhymes over Vader (I must admit, sadly... his "You need to wash up, dawg; here, step in my shower" just kinda took the battle right there).