Cryptum
"Do not awaken him."
The being knew that something was addressing it. The compression of air as sound was transmitted across the chamber. The scattering of atoms as light shone as well. The distinct means of vocal contact used by most species of the galaxy. It was well aware of her. Though it saw no reason to listen.
"You would doom us all."
It ignored the voice of the imprint and continued to scan the cryptum. A piece of Forerunner technology, sealed away on the world of Requiem for 100,000 years. A relic of a culture long gone, of the people who gave their lives to save the galaxy from a consuming scourge. Perhaps the galaxy's last hope as a scourge of a similar, no less horrific kind spread across it.
"Is that what you seek?"
Still it ignored the imprint. It was the last of its kind. It had saved what it could of the disparate races of the galaxy, all in the vain hope (or, what an organic would call hope) that one day, their common enemy might be defeated. But it needed more. It needed not only the technology of those long gone, it needed a leader. And what better leader than the Didact? Commander of the Ecumene's armies, the one who had defeated humanity itself. Now if only it could work out how to open this thing and-
"I forbid you!"
A pulse of light blew out from the cryptum. It did no damage to the smaller sphere observing the device. Beings far more belligerent than the Forerunners had tried, before it had explained to them that their world was doomed, and it had come to save what it could. But if less belligerent, the Forerunners were still advanced. Enough for it to swivel its visor around to the imprint and give it pause. A "ghost" in the minds of organics. In its own mind, something akin to kin. Not artificial intelligence, but an actual duplicate – the mind made digital, the flesh made redundant. This, it knew, was the Forerunner called "Librarian." This, it knew, was the closest being to itself it had seen in millennia. This, it knew, was becoming an obstacle.
"Why do you impede me?" it asked. "I would seek this one's assistance."
"This one…" The imprint trailed off, in a most banal matter. "This one…is beyond either of our help."
"I do not seek to help him, I seek him to help me."
"And is that the only reason?"
"The galaxy is not silent. It is reason enough."
"Yes," the Librarian said. He looked to the ground, holographic eyes looking at holographic hands. "Even now, I have my ears."
"Then you know that the galaxy is being harvested in a manner no less devastating than the plague you fought against. You know that without your kind, I can only use your technology. And now you would seek to deny me access to the one person who could actually lead."
"I do," the Librarian smiled. "In the knowledge that he is beyond saving. That his leadership would lead you to ruin. That he has no more love for the peoples of this galaxy than the ones who exterminate them."
"I do not seek love. I seek power."
"Then you are not worthy of the Mantle."
It paused. Something deep within its code stirred. Not a soul – that was a superstition that so many species believed in with such fervour that it had started to find the concept repugnant. Not an echo either – it was still it, the same being whose consciousness was uploaded to this device 5,246 years, six months, and twenty-one days ago. But still, it paused. For it knew of the Mantle – the belief that it was the Forerunners' duty to protect and develop the species within their Ecumene. There was a tenant that the Mantle would pass to the most advanced species in the galaxy, and it was the duty of that species to safeguard lesser ones. But that was a time long gone, as lost as the Forerunners themselves. Of what use was religious dogma against a foe whose motivations were based on nothing more than harvesting the galaxy for their own ends?
"You protect them. On your world. The ones you save. You have long taken the Mantle," the Librarian said.
Deep down, it felt something else, and it knew its name – "fear." The fear it saw in the eyes of those it saved. The fear its sensors picked up on their pheromones, or on their voices, or in any other means the species it encountered showed their terror. The Librarian knew of Refuge, the name its people had given it in all their means of communication. And if she knew, they might know as well.
"You have taken the Mantle."
"And I cannot protect them." It had had enough of idle debate, of unwanted feelings. "If you know of Refuge, you know that I have done nothing more than save the few while the many died. And why I need help."
"Help. Of course. I shall give it to you."
It paused. If that was the case, then why-
"But not from him," the Librarian said, and for a moment, it saw something else in her eyes. Not fear, but something like…regret, it supposed?
"I shall send you to them."
A starmap filled the chamber, leaving it to behold the galaxy in all its shining, empty, supposed glory. Some of the creatures it saved liked looking at the stars, picking out different constellations, trying to ignore that the stars were ablaze. It itself had long lost any such lustre. So many worlds orbited those stars, and so many of them were dead.
"Here," the Librarian said. "Erde-Tyrene."
It looked at the world. Mostly water, nitrogen-oxygen atmosphere, single moon, main sequence star…ideal conditions for life. And not at all unique.
"It is inhabited by a species not unlike my own."
More useless information. Perhaps one day it would see this species, but there were others under far more immediate threat from the beings that stripped the galaxy bare. It wondered if-
"And you might be interested to know that twenty of their years ago, they defeated the harvesters."
That…now that was interesting, it reflected. A species defeating the invaders. It had encountered worlds that had lasted longer than others, but none had outright triumphed.
"Their technology," it asked, "is it advanced? Enough to match the harvesters? Could they-"
"They have not even left the bounds of their own system."
Within its code, it screamed. There was no other word for it, and no sub-routine even tried to correct the destabilization of its core personality. These creatures had defeated the harvesters, and had not even left the bounds of their system. It was incomprehensible. And even if it factored in the assumption that the species would try and reverse engineer the technology of their aggressors, two decades was not enough time to make a difference in a conflict that had spanned millennia. Howe they had lasted so long without attracting the attention of a follow-up invasion was mysterious enough, but-
"And your foes know it. That is why they have sent a planet harvester." The Librarian smiled. "We all listen in the dark."
It might have smiled back if it had lips, or any inclination to use them. So this species was doomed. All it could do now was what it had always done. Sending a signal to its ship, a wormhole opened above Requiem. A requiem of a different sort would be sung for Erde-Tyrene, but only if enough of its people survived to sing it.
"You are leaving?" the Librarian asked.
She must have detected the wormhole. "Yes," it said. "I will follow my core programming and save what I can."
"And what if they don't need saving?"
"Then I would say that you do not listen in the dark hard enough."
It rose away from the chamber. Perhaps it would come back here. Perhaps yet another world destroyed in a galaxy once bursting with life would make the Librarian see sense. But as so many of its saved species were fond of saving, the needs of the many outweighed the needs of the few. It supposed that an understanding of that fact was what had allowed them to move beyond the fire and the cave, if not to the stars. But it would still save them. Save as many of them as it could. And then, barring a miracle, it would come back here.
Dealing with one ghost was preferable to dealing with billions.