Finished it, but couldn't find/reach all the puzzle pieces.
There's a lot to like here: the music's really good, the sound effects fit (though please leave that horrible scream when the mc gets burnt to death out of the final version), the moon orbiting mechanic's cool, and the puzzles feel good.
The artstyle of the world feels a bit like an old mmo, so I guess it fits, but it's not that good. It's not bad either. It just feels a bit unprofessional. I like the main character's sprites, though her face is weird, and the animation feels more like sliding than walking (I'm not complaining, I prefer that, haha). The UI is a bit ugly too.
The game feels unpolished too. There's a lack of visual effects for simple things, like water splashes or moons hitting things or getting a key or stuff like that. The camera work is the worst offender of this, where it kinda snaps into a new position (or transitions abruptly). Also, you have some bugs with collisions, moving along slopes and such, but I didn't find anything game-breaking during my playthrough.
There are a few puzzles where the player will most probably die, like shooting targets while falling into spikes. This doesn't feel quite right and may frustrate some players. It didn't bother me, because of the infinite lives. However, the death counter feels a bit insulting, haha.
Pointing the orbiting moons feels a bit counterintuitive (I expected them to shoot out in the direction they were pointing at), though it makes sense.
All of these issues don't really matter. The level design and puzzles are good and that's what's important. I had a good time figuring them out and enjoyed the background art and music too.
I'm not factoring in that you made this with your own engine, cause players don't really care about that stuff, but I commend your hard work! Good job to all who worked on this!
PS: an in-game cursor instead of the mouse would be neat!