I've been doing it very carefully, trying to collect as many power as possible, because I wanted to see what the bonus does. I've been having hard time over the past several stage, as I noticed everytime when I meet the mini boss, I'll get killed and lost all the collected powers and lost my bonus. This time, I employed save game when meeting the mini boss. And finally made it to the mothership with 12 power bonus. I know, silly me. I'm just an incompetent guy trying to score it and see what's the outcome, not a real gamer.
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