This entire game is a split-second risk/reward situation. You have to do so many calculations a second in your head without even realising it. When I play, and get good scores, I don't even notice what I'm doing.
That being said, I hate sticky keys.
After the end, i bought every block, and just made an army of weapons, methodically planned out for max destruction. When i replayed the boss, i destroyed him in 4 seconds. FOUR SECONDS!
 "Three Body Problem"){kind=icon}
 "Achievement Unlocked 3"){kind=icon}
 "Upgrade Complete 2"){kind=icon}
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