I like the moon level the most with the huge jumps. Water level feels too slow, maybe have a higher enemy (or obstacle) density. Juming sound does get a bit annoying and should be different for water (but I'm guessing time was a constaint here), Jumping could use some "coyote time".

Sorry, but I couldn't finish this one. 

The moon level is ridiculously more demanding than the rest. 

Flying aliens are possibly the most frustrating enemy in platforming game history.

I loved the game, it's varied and fun, but it left a bad taste in my mouth not being able to finish the level of the moon and see the end.

Really impressive how much you were able to do! The art looks amazing, but the background looks a bit dull (however still good for a short gamejam!). Sound effects match the theme but it would be cool if for example the sound effect adjusted to the jump height. Apart from that the idea isn't super original but there definitely is nostalgia and the level design is great!

Good game! it's impressive that you managed to make 4 different levels in such a short ammount of time! the only "problem" I found is that sometimes it's hard to read the number of lives you have (because of the color limitation) but no big deal. if you have time, consider trying my game too, i'd love to get some feedback!