Here is a little game we're going to play right now: name some of Iron Man's greatest villains (hint: Jeff Bridges is not a correct answer). Maybe you got lucky and recalled Mandarin; so how about giving a shot at naming some of Thor's greatest foes that aren't his brother Loki? Any come to mind? That’s all well and fine if none did, because there are only two groups of Marvel superheroes that have a decent gallery of rogues: Spider-man and X-men. Now with a new Spider-man movie approaching, we get a chance to see a new villain on the silver screen in the form of the Lizard. But who would be next? We've already seen Green Goblin, Doctor Octopus, Sandman and Venom all show up, but there is still room for more. Here are five Spider-man villains who could show up in Spider-man reboot 2.