Okay so I thoroughly enjoy spriting. I do so whenever I am bored, still as its a skill I'm proud of I always like getting better at it.
I figured rather than throwing up a specific topic each time I want crits on a sprite, I'd make a topic where I could put the sprites as I make them for crits.

At the moment I'm making a small 2D platformer, a simple project, but I want it to look good, here is the tilesheet for a rocky area,
32 x 32 per tile, tiles at top, example scene at bottom (including main character):

[size="1"]All Content for the purpose of the 2D platformer "Telli" are protected by a creative commons [size="1"]licence
Do not use without my consent.


Any and all crits appreciated,
Thanks in advanced,
Bombshell

It looks presentable as it is already 

But there's always room for improvement. Three things came to mind:

• Make use of Anti-Aliasing*, always.
• Bigger contrast would look nicer; it'd give more depth and you can still do it even with palletized graphics (look at the great contrast these screenshots have). It's all about the color-choice. With a bigger contrast you can make richer textures and give those stalactices more cylindricalness.
• Did you use reference pictures, like from rocks, caves etc?
  * I've collected some resources on pixel art anti-aliasing for you, but you can dig up more underground stuff if you research further:
  http://gas13.ru/v3/t...ntialiasing.php
  http://wiki.wesnoth....lias_Sprite_Art
  http://www.natomic.c...ks/mpat/aa.html

I know how to anti-alias, but the sprite are meant to look retro-ish. I'd rather only anti-alias where the aliasing is highly visible.
I've messed with the pallet and made background tiles.

I like your changes to the pallete, and those shaded mountains look very cartoonish, so good job.  

That baby-blue sky made me regurgitate, however. Perhaps use analogous colors?

I get what you're trying to do with the clouds, but I think they should have less definition in the middle - right now they have a slight look of "alien cocoon" or something like that, and I can't really tell where the light is coming from.

I think they should look more like this:

See how there's no shading for the best part of their center? this gives an impression of softness.