Lightning speed and athleticism vs. raw toughness. But, I gotta say Sonic will be just too fast for Big, Bad, Mario to catch. Gotta be Sonic. Mario is immoral, a symbol of evil. Sonic the video game was better than Mario, the cartoon was better than Mario, and well, the merchandise is too.
Lets look at the facts.
One stupid plumber vs. a hedgehog. They hurt when you stomp on them. This is sadly mario's basic form of attack. Lets see what he has to say when he jumps on top of sonic. He will mutter a string of expletives unsuitable to younger viewers.