Hege makes plenty of pixuls

[Gors]

the most blatant problem is that you use way too much colors.

more colors =/= good pixelart. In fact, pixelart is a kind of art where you economize stuff. Of course, you're pretty much free considering that the computer can handle millions and millions of colors but that doesn't mean you need to pick each color known to the human eye to make your work.

You could edit that 4 shade ramp in most your sheets to have, like, three, and recycle them instead of making new colors. Also avoid using black in pixelart; it eats space and may trun your work in a black blot (e.g. your dragon).

You may also use a different anatomy 'set' instead of using Sonic's. Humans do not have skinny limbs, ball heads and huge feet. Using a more 'correct' anatomy will make it more original, as the Sonic sprites are too overrated by now (also most your chars have the same pose; try varying them. Posing is one of the ways you can convey someone's personality after all).

Make sure your outlines are smooth. Jaggies make your outline very messy, and it's a no-no in p. much everything. In addition to that, stop banding. It doesn't convey volume at all and makes your sprite look like crap.