The difference between what you did and what you referenced, as far as I understand, is in the linework. This is not a simple outlining work: the linework needs to convey depth and volume through varying thickness, and there are also black masses to contrast the flat colors to have a minimal level of lighting information. Flat unicolor can work, but you need to work on the linework extensively for it to work - it'd need to work as a B&W picture, almost.
You could try adding some black to hint at general volume/object connections (ground to object) and light indication (for instance, on top of the tree trunks/below the foliage to show simple shadowing). Working on the linework will be harder if you're not using a drawing pad/tablet, but that's probably what you'll need to use for single flat colors.
If you go with two shades with more regular (dare I say digital) linework, that's the more usual treatment, and it'll be a technique closer to cel-shading, so maybe research more in that direction to get that effect?
In either case, the one thing you'll need to make clear is lighting, as that's the big part that'll show volume through limited color! In your example the lighting is a bit too plain (coming from the overall top, but not overly defined). I'd suggest going for an angled lighting to have larger and displaced casting shadows. That's what I do for Honey anyway, as I do two-shading only as well!
Thanks for the suggestionsThe problem is the linework (also if you are going to emulate that style, body shapes and faces are also important to be similar).
IMO it would be better to do it drwaing it instead of pixelart, I think it would look much better.
Also look at Kennedy's suit and and super man's shoulder and head type of linework shadowing. That needs to be present if you want to do that type of art, its a lot more difficult to reperesnt that type of shadowing with pixelart, as there are going to be lots of interior lines. Look like he uses base colors and uses the linework for shadowing. I already see in your trees and rocks too colors (1 for light, and one for shadow) that is not repredented in the image you showed.
EDIT just re read and saw you already knew that about the shadowing outlines not being ossible with pixels. As I said, if you can do it, it would be pretty cool that your game emulates exactly the comic style you want to go for. ANd depending of how you want to animate your game it can be easier or harder. Frr me, scenearios would be much easier doing it in that style than with big pixelart.
Damn i was writing my answer when i realized that i sacrificed the art style for the sake of other things(for example for an easy shadow management i decided for that light and little shadows), but now i understand that i was stupid.
About the graphics style itself, i tried to use black to make shadows and volumes, but on a less than 128 pixel tall sprite of a human the result was not good because it loses too many details, that's why i decided for two shades for everything relegating black only to outline and details.
Now i'm undecided, for story screens i will use the comic book look for sure, for the game i don't know, for big elements like trees i can do it, but for small sprites...
I need to think about it.
Thanks, but someone from the Italian GAF thread had already translated the text. Sorry.
Everything is translated, thank you all for your help!
Wait there's an Italian gaf thread?!?!?! :O