@Allsmylz on the map screen, areas are marked with the color of the medal you have. Also, when you select a level (and before you start), you're shown the criteria for the medals and which you've completed.
It would be nice if you could change your body parts in the research lab, instead of the incredibly terribad Workshop interface (which shows you abilities' icons, but not a tooltip or anything telling you what they do!)
@Sellyme BlueWolfSerenade is sort of right in that we're seeing slices of the images one pixel wide at a time, and that one-dimensional (or even two-dimensional) objects only exist in the abstract. He's also totally wrong in that with a uniform (arbitrary) width of each slice, the horizontal range is all we actually care about in each slice, and that's one-dimensional information.
The people who say there's no story boggle me. You don't need dialogue to tell a story, and -- as chromatose said -- for anyone familiar with the myth, there's the "eureka" moment.
Nice graphics. Poor gameplay. After the first fight or two normal punches and kicks are pretty much useless for everyone without a very good range (Satan and Moses), and the timing on the combos is annoyingly finnicky.