It's pretty interesting. I like the premise of the game and the way the monochromatic terrain makes all the objects of interest stand out.
The movement is a bit frustrating sometimes. The slow horizontal acceleration is such that I have to peck the buttons rather fast when I'm near spikes to get next to them and for some reason it feels like it's more effort than it should be to just stand next to the spikes without gliding onto them. And the instant vertical acceleration and gravity speed make it so the time window to successfully jump up through a narrow ceiling gap to a new level is short. I feel like the most interesting part of the game is learning what items to use in what order in order to solve each puzzle and concentrating on the run'n'jump aspect feels like a distraction as a result.
I had to stop on level 4 because I couldn't figure out what the purple button-like things on the right are. I broke the vial to cross over and jump around near them myself and then I tried again and carried the turtle over and threw it at them and got munched instantly. Already I can't think of anything else to do on that level.
Also while I was writing this, the turtle's pacing brought it off the spikes over to the buttons on his own and the music cut out and won't start again.
But overall, good job. Thanks for making this.