Pretty nice pixels there~ I see room for great growth. Few suggestions to help you take it to the next step.
When saving pixel art, save as .png. The quality won't be muddled if you would.
And try to make the outlines only 1 pixel in width unless you're denoting line thickness. That will prevent that stepping stair jaggedy outline look and create more smooth curvature.
Example of why 1 pix width can still do the trick:
![[User Posted Image]](http://i42.photobucket.com/albums/e341/terrorofdeath8/holyepicsprite.png)
Having a 1 pixel width for the outline will help make a smooth transition in curves, especially when you scale down to %100
![[User Posted Image]](http://i42.photobucket.com/albums/e341/terrorofdeath8/sharpened.png)
See? The 1 pix width helps the curves look natural and not staggered like the way the body of your Eruptor sprite looks. The bits of 2 pix width around the ends of my sprite's hair still help the hair have a pointy quality without making the overall sprite feel weighted.
Art and game (c) Ronan Castel
I just helped make assets for his game. But he owns all rights to it~
Not the best sprites in my arsenal, but good for teaching.
You have a good starting potential for sprite art :3 That's why i give you tips. Hope I helped and keep it up.