These are the Four Color Heroes. They are meant to be bright primary colors – why are they do dark?
M. D. Jackson has been drawing since he could first hold a pencil. He has been writing for so long that he has, in fact, developed an alternate personality named Jack to handle the fiction.
His work has appeared in numerous magazines and on the front covers of many books as well as in the pages of Amazing Stories Magazine. You can also see a lot of it at his gallery.