I very much like this. It's intuitive, and a nice take on the virus game type. The addition of nice graphics and a good soundtrack make the game. However, it only gets 4 stars thanks to a game-breaking bug; occasionally on medium difficulty, the computer will not take 'damage' during a battle. For instance, on the level with 2 turrets on each side and a warp gate in the middle, we each had the three identical planets on our respective sides. We both committed everything to a battle at the warp gate, and my ships were destroyed. However, I noticed at the end that there were 91 enemy units at the gate, which should have been impossible. I quickly paused and counted and saw that I had 31/110 possible units (the ones which had spawned on the planets during the gate battle), while the computer had 110/110 units. Either there was a bug that wasn't registering damage to the enemy units/lowering the unit count or there was a bug that reset the enemy unit total to it's previous value after my units were eliminated at the gate, but that sort of bug completely breaks the game since you have to reset the level in order to win after that. The same problem occurred on a few other levels as well. Overall pretty good! You took a simple idea and executed it very well!