Well, did you find all the lore? Sometimes that can be really annoying because it's invisible to your combat visor. And if you don't have 95 missles, 7 extra health bars, or 400 ammunition for your other weapons, you're missing power-ups. That's all I can suggest. Or, if you've tried a million times and are ready to give up, you can use an online walkthrough.
Imperialist
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(o'.'o) This is Bunny. Copy and paste Bunny into your
(")_(") signature to help him gain world domination.