It's Not Easy Being Green
It suddenly occurred to me that comic book characters are some of the most racially diverse group around. I mean, they have people with blue skins, red skins, and even silver skins. And for some reason, there seems to be an over abundance of characters with green skin (or scales, fur, etc.) as well.
I've tried to be as honest as possible, counting only those characters who are naturally greenish in hue and not costumes or armors. I ultimately decided to count robots who are predominantly green as well and stayed away from the Pokemon creatures as I felt they already have so many lists already dedicated to those guys.
I also tried to limit myself to include large groups too. For example; I stuck in the Teenage Mutant Ninja Turtles as ONE entry rather than four separate ones. Same thing with some of the alien races; I added some of the more important and major characters and considered that the more minor and miscellaneous ones fell in the alien species entry. Some guys are in here simply because they used to have green skin but were de-powered or something altered it. Basically though, if they WERE green for a while, then I decided that they counted too.
I should note that I do not know a lot of these obscure characters, in some cases I am simply going by appearance. If their green hued appearance is because of a poor image scan or a costume, then I sincerely apologize. Feel free to send me any corrections or additions and I will gladly add them.
If the color red is more your speed, then I have another list that features red hued characters here.
Or if you're feeling blue, then Retodon8 has a similar list to mine that features characters that have blue skin instead!