User blog comment:ElvisGoopBuysDogsForever/Fu Manchu vs Ra's al Ghul. Epic Rap Battles of Fictional Characters Season 1/@comment-27286780-20160817211944

I'm bored so time to geuss some hints I guess

Doctor Doom - his real name is Victor and is a doctor so obviously hinting to Doctor Victor Frankenstein

numbers - It's counting up. Sesame Street has a character named the count obviously hinting to Dracula

Leonidas - I've gotten no clue at the moment.