The sprite work on this is very nice, as is the music. Really good aesthetics.
It would be nice to tell the player that they can double jump. It never occurred to me to try, and I got stuck for a while.
Is there any way to regain health? I'm not very good, and I keep having to restart from the beginning.
I absolutely love the way the slimes pop like a balloon full of paint. That's very satisfying.