Taking a short break from the big stuff to make some more of these. They're fairly simple, just two tiles for ground per mockup, plus one destructible ground tile and one that crumbles under pressure. Also two tiles for water and three for ladders (bones, cactuses, vines, etc), plus two tiles that just serve to add a bit more variation.

Those white bird-like things in the swamp seem a bit out of place, I guess. I meant for them to be more ghost-like.

I haven't yet figured out how much I should brighten those darkest colors.
The last one is missing monsters. Any ideas? I only have some pointy icicles, and I don't think my polar bear is very interesting, so I haven't finished it.

The last two still need a bit of work. The rocky tiles are giving me a bit of trouble in the first one, since I don't want it to look too busy. Just haven't gotten around to the desert mockup yet.

I'm also making some minibosses, which are 32 x 32 pixels in size.

What do you think?

Edit: The levels so far...