You know, there's always that one villain who has a lot of potential yet never gets enough screen-time. Which bad guy, that fits this description, is your favourite? Is this villain of choice of yours really underrated? Would you like him to be the main villain in future stories? My pick would have to be the Human Fly. This guy started out as a massive badass who could take on Spider-Man and hold his own, similar to guys like Scorpion or even Venom, but he slowly became more and more threatening due to his mutations making him more fly-like in both appearance and behavior, until he turned into a complete monster, a cannibalistic ex-con and kidnapper who returned from hell and killed his girlfriend. He's still roaming around New York, torturing and eating people for fun. Although his potential has been well exploited, he's not a main villain anymore, and he totally should. He's still very underappreciated, and the fact that some diehard comic book fans don't know him is unacceptable. The Fly rocks!