A very well mix between shooter and puzzle indeed.
The gameplay is very unique and flash. Shooter + Puzzle is a nice mix up, and it performs very well here.
The music and graphic are just wonderful and polished. It builds up the atmosphere perfectly.
The flaws of this game maybe are lacking upgrades, "invulnerable time" when being hit, and the movement penalty for carrying a cube.
The later levels just being surrounded by swarms of cells and bullets, the lack of "invulnerable time" and movement penalty makes this game VERY hard even for just survival, not considering building combos.
Locking Levels can add to this game too. It is strange that you can play the last level right away at the beginning.