Underdog vs. McGruff the Crime Dog! Who Wins?

McGruff walked down the seedy street, tightening his trench coat around him. The was crime afoot. A new drug had hit a streets, a drug unlike anything seen before. It came in pill form and was so powerful, it was known to give it's user temporary bursts of superpowers. The side effects were horrible to behold. The user's eyes would light up like an explosion, their pupils would spin in circles, and once McGruff had sworn he'd seen an American flag in their eyes. McGruff had been frustrated by this case for a while, but this morning something had happened the made him determined to end this blight on his city once and for all: his beloved nephew, Scruff, had become addicted to the pills.

There could only be one suspect in McGruff's eyes: the canine crusader Underdog. As hard as it was to accept that a mutt who'd so tirelessly championed justice could do something so dastardly, it was a well known fact that Underdog drew his powers from the same kind of pill, and even if he was not the distributor, he was most certainly the source.

The trick was finding Underdog. It had taken a while, but after questioning Underdog's known associates, like Sweet Polly Purebred, as well as the head of the drug operation, Riff Raff, he had finally learned Underdog's secret identity: humble, lovable Shoeshine Boy. McGruff should've known; there weren't that many talking beagles in town, after all.

McGruff turned a corner and there was Shoeshine Boy, a friendly smile on his face, hard at work shining the shoes of a customer.

"Stop right there, Underdog!" growled McGruff, "I'm taking you in for questioning, and I'm confiscating that ring of yours!"

"I know this case may seem airtight" said Underdog, as his zipped into a nearby phone booth, emerging an instant later in costume, "But all your facts are not quite right. I'm not the fiend behind this plot! Bar Sinister is the man you sought!"

"A likely story pup," retorted McGruff, "now are you gonna come quietly, or am I gonna have to take a bite outta crime?"

You decide, dear readers! Dog vs. dog! Who emerges victorious?