Nice concept, and quite fun to play. The balance feels a bit iffy right now though - after a few tries I ended up making something with a few flaks in front and lots of turbines, and the game never threw anything at me that could counter it. There wasn't even an incentive to keep expanding because that would've only added more attack surface for little or no benefit as well as making navigation between obstacles harder.

Also worth noting, I ran into an out of memory error with the WebGL version:
