Very nice! I had a lot of fun with it, and the art was really cute. I love the use of 3d art in a 2d environment like that, you made that look so smooth.
I did get stuck for awhile, until I saw you could stick Pebbles together to freeze them. And then, only at the very end did I see you could stick pebbles to the sides of things, too. But once I figured that out, it was a lot of fun to climb the tower.
I do appreciate the easy mode, I tried hard mode a bit and... Man that water is fast. I am not good at placing the Pebbles onto the sides of things, so I basically drowned before I even got anywhere.