I adore your art style and the color palette is great! :)
from a technical standpoint you should have used a Y-Sort Node, so that the player is not rendered below the slime box. That's a bit confusing at first.
And there is not much variety in the gameplay at the moment. Most levels felt the same. I guess you have planned a lot more, cause I also don't see how the repair of the pipes pays out.
Nevertheless I had fun playing your game. Great work! :)