A good start for a puzzle game but I did have some issues. I can't seem to beat level 7. Those blocks in the middle are too high for me to shoot. I tried stacking both with the stacking button and by just jumping on top of my other cubes but I still couldn't shoot it. Maybe this is unintentional, but I really think you should make stacking more than 2 cubes a thing. It would also give you more opportunities for puzzle design as well! The music was also too repetitive. It has nice chord choice but it could really use some fleshing out. Maybe try a driving hi-hat line and a fun little bass line to give it more life but keep it more mellow and out of the way.