These are the first 3 enemies I've mocked up for my game, which goes for a Kirby: Nightmare in Dreamland aesthetic. One throws its glasses as a boomerang, one throws dynamite from its head and one lulls the player to sleep with music.

The piper on the right is obviously the most complex, and I'm new to doing complex shading, especially with clothing. Constructive critique would be great for all 3. Thanks!

Thanks for the reply! I made some of the interior 'blacks' softer on the piper, but I feel that a hard black outline helps readibility on the glasses and bucket outlines. Might change this later.

What do you mean by tone colors? Do you mean something like hue shifting? I went through and redid each sprite's color ramp to have more consistent hue shifting, hopefully colors are more readable now.

Also tried to avoid get rid of banding on the dynamite. It looks (to me) a little noisier now, I think I'm still struggling to convey a perfectly cylindrical object viewed head on. Any advice for that?

   

Well the first two definitely won't have arms, that's just part of their designs.

The third (Squeeks is his name) might have arms soon, I'm just having trouble getting them to stand out against the garment. Even if they're the green skin tone, the blue tunic color, or the beige stocking color they take a lot of readability away from the sprite, and they're so thin that an outline is hard to make. I'll work on one to post soon to show

Updated Squeeks a bit, tried out arms. Still needs a bit of work on the body shading, but it's getting better.

Still wondering what people think of the new dynamite shading on the Bucket...

Thanks so much for the tips and retouches! I'm very new to drawing/pixel art in general, so diagrams like those spheres really help me understand lighting better. Thanks! 

Your new work is much better

here's my edit. I tried to keep your style as much as I could. light could still be improved even more but I would lit it somehow like this.