Maybe there is not necessarily a good or bad in the universe. Take a look at our enemies they use very similar forces just like us, such as solar, arc, and void. Maybe what we call light and dark are just two sides of the same coin that we choose to call good. We just call it darkness because its being used by other races to harm us. For all we know the darkness could be the same race as the traveler and they are now fighting each other for unknown reasons. But I guess only time will tell the truth.