Smash Sprites!!!

[Gors]

And here you have learned 3 things:

1- Shade efficiently. A good shading with volume in mind will help you convey tridimensionality better (that's the reason of shading something; it doesn't exist just because);

2- Upscaling involves adding more details the original sprite couldn't handle;

3- look for references. Don't be demotivated for having to look for references. I do that all the time, and don't focus on one source either: Natis picked an image of Mario from another game to help construct the sprite, and that's how you should work.

Happy spriting, and keep practicing