Very nice! I think there is a bug with the timer not restarting in between plays, but it is fairly small. The one thing I would change is that I think rockets should be cheaper (15/30 instead of 50/100) since otherwise it's too easy to just replace DNA/ block your entire helix with 3 shields, and I think it would make the game a lot more dynamic if rockets were flying everywhere. Other than that very nice and fun!