If you're having trouble with money or experience:
1. Add a high level friend.
2. Do the most difficult COOP CHALLENGE you have available
3. Make sure to DIE BEFORE completing the 5th wave .
4. REPEAT!!!!
It sure made my life easier! :D
I really love the game!
Would it be possible to include the upgrades of the ships, when we hover the mouse on the screen in the campaign? Sometimes it can get confusing, especially at higher levels where you need to customize your armory more often or change strategy midgame to defeat the harder enemies. :)
Thanks!
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