Very neat idea, would be a good base if you keep at it. It starts feeling repetitive after a few levels, without much being really changed up. The menus are also a bit buggy - I'm not sure what caused it, but every time I started a level I was paused and had to hit esc twice to open then close the pause menu and let the level start playing. This got to a point where the text "paused" was permanently showing on the screen.