"Energy Orbs are simply the result of vile ways the Invasive Worlds use to immediately harvest the resources of a world. They will hunt down their denizens and squeeze them out of Source Energy to be consumed. While it produced impure Source Energy, they naturally came up with methods to expel those impurities over time."
"I'm certain some of you watched that method happen in your worlds. Even though a lot of them want to assimilate the whole world to bring progress to theirs, they won't bat an eye massacring more than half of the denizens' population. The same can be said for those conquering a world to turn it into a Slave or Mine World. They will only occupy it, corrupting a select who will do their bidding. While waiting for the natural formation or discovery of Energy Crystals, they will use the denizens as an early resource, taking only a percentage of them to turn into Energy Orbs and then let them breed again."
