Really cool idea and execution. I love how you have to move the towers to combine them into better ones and I though I was being baller when I was getting level 4s and 5s before the wave started! Then disappointing when it I was unable to stop a single unit though I had high powered (or so I thought) turrets. Perhaps starting the waves a bit easier it be nice. Eventually I filled all slots so I was stuck with why I had and at times it felt like I was losing some of the 4, 5, and 6s level turret. Still, I had fun just figuring out how to power them up. :D