Played the first 5 levels so far (15 is so many for a jam game!).
This is the most novel mechanic I've seen in a while.
Moving the block to shake the world feels awesome, and I suspect the mechanic could have a lot of future potential beyond what is in the game already (unless the 10 levels I haven't seen yet exhaust all possible interesting uses of it; but I doubt that).
Two things I didn't like:
1) while the music was generally nice, occasionally it would get randomly louder and higher pitched, which I found to be an annoying interruption, especially in a puzzle game - like "shut up music, I'm trying to think!";
2) I was disappointed that level 5 didn't actually require the main mechanic to solve, and it seemed like it was less about being clever and more about just having a lot of steps to complete.
Overall great job though!
This and the turtle game both shocked me with the level of polish.