My only problem with this game is you get punished if you ever start winning the battle. Instead of trying to win i'm instead trying to make sure i'm pushed to my tower so it helps me fight
Freeze Tower broke the game for me, By level 50 it was dealing 90,000+ damage a shot, slowing to 0.083. Problem is the bosses didn't take any damage, so I sold all my towers but then the bosses didn't move at all...
Too easy for its length, playing the first 3 levels felt fine as they are suppose to be easy but then the difficulty just stagnates with your health staying 90+ for nearly the whole time.
To get the last depth trophy, use a nitro while facing straight down when you have a depth of 2460ish. As you normally hit too much pressure at 2500 without the nitro.