It is said that to be reborn in the light, one must die a very terrible death. It is how the Traveler destined it for each Guardian, it is in the Lore, written, scripted and worshiped. In its dying breath, the Traveler created what we call 'Ghosts', small mechanical beings that serve as scouts, mechanics, Librarians. They guide their chosen Guardian companions in their quests to reclaim our solar system from those who dare to try and take it. They search the ancient dead, seeking those who can wield the light as a weapon, those with nothing left to give.
A small light in an immense amount of darkness beaconed to any who would listen, calling out, searching for one that would take to arms. One to fight the darkness with the light. Its shell would twist self-consciously as it scanned face after face, or rather, skull after skull, finding none that suited his need. 'There is no light.' It would think to itself, bobbing slowly away from the mass grave. Perhaps.. another day. It was so hard to find the correct one, he had listened to many of stories, researched many article logs. Some Ghosts took years to find theirs, and he knew he was not the only one.