This one had an interesting concept but unfortunately bugs seem to drag it down. The first one I noticed was that if you move a block thats already place on the map the "Defenses Left" counter continues to decrement into the negative. This resulted in my being unable to place more blocks on the following level.
However I was not even able to really play the net level as enemies cubes kept moving towards my cannon before I had even pressed "Ready!" and I died as soon as I selected it. Even more strange was that when a similar bug started I simply clicked ready before they could get to me and I was able to pass 3 levels just by rapidly clicking ready. And then on the 4th level of this strategy I of course died as before, since the enemies had advanced far enough to kill me.
Also this is a very minor issue compared to the two bugs above, but the collider area for the purchase buttons in the shop doesn't seem to cover the top 25% of the buttons.
As for the game itself, its a neat idea of having a sort of tower defense game that relies on bouncing cannonballs at enemies, and the changing colours to denote health levels is a cool touch. The lack of sound is a bit disappointing, even some simple blips and bloops could have been nice.
Core gameplay is solid, but a hotfix would have been nice for the bugs, and a bit more life would be required for me to put this in the "So bad its good" category.