It was just a small wish: All they ever wanted was to live with their master and their friends as those uneventful days passed by, to see him grow up as he chased his ideals by his own strength.

To become an ally of justice; a hero who can save everyone without having to sacrifice anything.

That's why they will fight, even if they have to taint themselves to make his wish come true. They will walk down this path, no matter how dishonorable it may be. But it is not for the sake of the Grail, nor for the sake of the Book of Darkness.

They will fight for the sake of the boy that has made them his family, and who believes that , even now, they still can be heroes. That is why they can allow themselves to fall into darkness, to besmirch their honor, and to drown in disgrace for his sake.

Because they were never real heroes to begin with.

Prologue

rebirth

New Calendar 0054, TSAB L-class cruiser Hestia, currently transporting the lost logia known as the "Book of Darkness."

Death reigned supreme on the Hestia, as the eldritch abominations spawned by the tome devoured both man and matter in the artifact's attempt to escape from those that had attempted to confine it. It had managed to take over control of the transport ship's navigation and weaponry after devouring the sub-bridge of the Hestia, including control of the experimental Arc-en-Ciel. The weapon's charge-up sequence was immediately activated while the Hestia slowly turned its bow towards the rest of the fleet. With the weapon now pointed at the fleet, the Tome now possessed the power to destroy the approaching enemies with a single shot, before using the information assimilated from the ship's database to find itself a new master.

But its plan was soon thwarted as the enemy dealt the finishing blow to the Hestia before the Book could even fire its own weaponry, as captain Harlaown stalled the program as he delayed the deployment of the weapon until the very end. Distorted space-time tore the ship apart after Admiral Graham issued the firing order from his own ship, forcing the Hestia and any surviving crewmember to face the full strength of the Arc-en-Ciel's discharge. With a tremendous blast any remains that escaped the dimensional disintegration were shattered across the cosmos, destroying the physical form of the Book of Darkness along with the ship. Only fractions of the tome remained in the material universe, with every scrap of energy harvested from the crew of the Hestia lost in the destruction of the vessel . It left the tome with barely enough power to maintain its very existence, and all it could do was remain in limbo as the immaterial parts of the book slowly started to gather.

It would take ten years before the tome's programming would once more regain consciousness.

Ten years later, Downtown Fuyuki, as the fourth Heaven's Feel comes to an end.

Death reigned supreme in downtown Fuyuki City, as downtown Shinto burned in the inferno of unholy flames which had sprung forth from the wish of Kotominei Kirei as the holy grail made itself present. A bright flash of light closed the curtain on the fourth Heavens feel as the holy blade Excalibur tore through the materialization of all evil in the world. Without a vessel to contain it the innards of the false Grail were promptly released on the ground, annihilated everything that lived in the area. The shrieks, cries, and moans of people whose flesh melted away under the unflinching firestorm turned the small district into a landscape fit for hell.

Amongst the flames a small boy almost crawled away from the death and corruption, his hands pressed against his bleeding ears as he tried to shut out the cries of pain and help. The color of his flesh slowly turned from its normal color to a gruesome reddish color, before it turned a gruesome black. He whimpered as ash filled his lungs and smoke burned his eyes. Even so the boy continued to walk, stumbling forward until he could barely move. He ignored the voices around him, hellish whispers beckoning him to save those who had already died, as others tried to convince him to lie down and embrace the warmth. He refused to look back, for the sky behind him was filled with darkness and the ground was filled with the flames and with the dead and dying.

He just had to keep moving, until someone would save him.

And so the dying boy continued until his legs could no longer support him.

Slowly the consciousness of the Tome spread itself across the universe, as the incorporeal program continued its search for a new host. The program had been forced back into a state where it could barely manifest its powers in the physical world. The tendrils of the master search spell burrowed themselves through space as it sought out large concentrations of magic, a sign which would guide it towards the next mage who could become the master of the tome and supply it with the power it so desperately sought to continue its existence.

Eventually it detected a large concentration of magical interference, an event with magic so highly concentrated that it was strong enough to pierce the dimensional barrier at the source of the phenomenon. Computing the finding, the Tome swiftly calculated the chances for finding another suitable location, after which it set out a course. It was reasonable to assume that these high levels of magic was an indication of a large magic-based society, containing many potential powerful hosts for the tome, based on the size and intensity of the signal it had picked up.

With its current reserves already dangerously low, it didn't find any alternative options. And thus it sprung into action.

"Dimensional transfer"

The moment the book appeared in the burning city it knew that it had made a grave mistake. The phenomenon which had lured it here almost immediately collapsed after the Tome's appearance. As the dark monstrosity vanished from the world the cursed sky returned to its normal state, before ash and smoke shrouded the stars from anyone watching from the ground.

it had erred greatly. With its reserves depleted to its very limit it could only manage a very localized search to find a suitable master to anchor itself to, an action which would be vital on this now magic-barren land. In the worst case it's programming would completely lose any chance of interacting with the material universe for decades, until the book could siphon enough prana from the planets own field to resume basic functions, a feat taking a minimum of half a century, assuming perfect conditions.

With its power at a critical low level , the Tome found itself almost on top of a potential target. It could not make out the host's characteristics at this point, but it contained an acceptable amount of magical energy for the tome to sustain and repair itself.

And thus the Book of Darkness, lacking any other means for remaining in the world, bound itself to the only magical human it could locate.

Only to find out that it had made its second mistake that day.

The boy had already given up on surviving. All he could do now was wait for the moment death would release him of the burden of carrying his wounds and pain. As his body started to die, his mind burned away. He didn't even notice as somethingentered his body, anchoring the ethereal essence of the Book using his physical form.

It didn't matter anyway, he had already given up on surviving at all.

The tome quickly discovered that it's only hope of remaining in the material world had already run out of time. realizing that it could no longer take any action to preserve itself at this point. It prepared itself for its newly acquired host to pass away, draining as much energy from the boy as it could to shave off a few months form it's regeneration cycle before-

The man crouched down, placing an object on the boy's chest.

A golden light enveloped the dying child.

The Book stopped its attempt at draining the host of its remaining power as an unknown power entered the boy, binding itself into the very structure of the host alongside the Book. The boy's vital functions were rapidly restored to near perfect health as the golden power forced the host's cells to regenerate at an unnatural speed, feeding the cells with its own power as they rapidly multiplied to restore the damaged organs and tissues. Unable to recognize this unparalleled power the book reached out towards it, trying to force a connection with the alien source of magical power.

It's attempt to probe the unknown object proved almost disastrous, as Avalon responded to the incursion by flushing the connection with the same power which had been feeding the regeneration, but which now brutally destroyed the anchoring constructs that the book had placed inside the boy's mind and body. In the end the Tome was only able to prevent its own destruction by minimizing its own activity.

And as the man carried the single life he had been able to save towards the hospital, the two powers came to a standstill. Avalon healing powers slowly came to an halt with Saber's remaining prana spend by the scabbard , leaving the immaterial Tome barely hanging onto its host. The physical remains of the book remained behind at the scene of the boy's rebirth, where they soon fell decomposed into nothingness.

The tome had barely survived, and the physical vessel had once again been lost. But even now It slowly siphoned power from its now master, showing enough restraint so that the other occupant of the boy's body remain dormant while the Tome slowly gathered power once again.

It was content with the situation. It had prevented an immeasurable delay in its reincarnation and had obtained a new Master, one which carried an unknown magic alongside the Tome itself. As it regenerated it would obtain this power, as it worked towards its own completion.

No matter how long it would take-

"Bereidschaftsmodus activiert."

It would prevail in the end.

Fate/Night Sky

-666 empty pages remaining-