What really makes this game work is that you considered gameplay in the application of upgrades. Giving us right, left, and rear guns allows us to take the evasive maneuvers necessary to avoid getting hit while not forcing us to sacrifice offense.
The thickness of the pieces' outlines make it really difficult to place them accurately, especially while avoiding bombs. I'd like it if the outlines were diminished, or at least changed to a color that was easier to see.
I decided that I absolutely had to beat challenge all the way through, but was eventually left with the simple realization of fact that it just isn't possible. With the right strategy, you can jump levels quickly and make yourself strong enough to just breeze the first thirty levels. But then you suddenly realize that you are no longer gaining experience from killing enemies, and since stalling at control points isn't a viable option, you've essentially reached a level cap. This means you are stuck at a level that just isn't high enough to survive. I loved this game. Now I think it is utter bull.
Another health suggestion: don't have the pickups disappear over time! Since they only really spawn from destroyed bases, they are usually in the middle of hoardes of enemies and to try to pick them up would only result in losing more health. Maybe this is just meant to make the game more challenging, but I really just find it to be inconsiderate.
I'd like to get money for making it to different heights. The money pickups are too sparse and difficult to get, especially when shooting is the only control method and you fly by the money so quickly.
Make the special weapons attack faster. I've found that using the croquet mallet, golf clubs, etc. is actually a bad idea because they attack so slowly.
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