I shouldn't have to point out how big the universe is but somewhere out there is some unimaginative potential, that once seized, can/will make a species stronger and faster. Maybe it's alien tech, maybe it's something natural. Someday it's inevitable. Once superiority is fully established and countless legions are organized, they will simply hunt out of boredom. The other species will be wiped out because a truce/mutual agreement will not allow both to exist. If both sides find similar tech and are both organized, the dying that remain will just wither out of existence, via mutual destruction. Anyway, point is, it's all about perspective. Is the Traveler evil? Ask an Acolyte. Of course all these alien freaks are the true evil ones, from the human perspective, which is how we relate to it. But it is kinda depressing.