Games Like Super Space Crystals

The Fraternal Brotherhood of Evil Magic Space Robots has conquered most of the galaxy!  Luckily for you, their reckless expansion has left the Magic Space Crystal fields mostly unguarded - and vulnerable to plundering.  In this case, "mostly unguarded" means protected only by a few million Evil Magic Space Saucers - as opposed to the trillions that infest the front lines of the war.

You've been granted a Personal Privateering Permit by the Elite Order of Magic Space Wizards, and you are now free to fly your custom StarFrame Harvesting Space Cube(TM) drone past enemy lines, to gather Magic Space Woo-Woo for the war effort!

You'll be well-compensated for putting your equipment at risk, and this will allow you to purchase some much-needed upgrades to your weapons and engines.  And who knows what other wild contraptions those crazy wizards might be willing to sell you - maybe you could get something to control gravity or mess with time....